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) 1996-2026, 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/amapi.h"
27 : #include "access/genam.h"
28 : #include "access/htup_details.h"
29 : #include "access/skey.h"
30 : #include "access/sysattr.h"
31 : #include "access/table.h"
32 : #include "access/tableam.h"
33 : #include "access/xact.h"
34 : #include "catalog/index.h"
35 : #include "catalog/pg_collation.h"
36 : #include "catalog/pg_constraint.h"
37 : #include "catalog/pg_namespace.h"
38 : #include "commands/trigger.h"
39 : #include "executor/executor.h"
40 : #include "executor/spi.h"
41 : #include "lib/ilist.h"
42 : #include "miscadmin.h"
43 : #include "parser/parse_coerce.h"
44 : #include "parser/parse_relation.h"
45 : #include "utils/acl.h"
46 : #include "utils/builtins.h"
47 : #include "utils/datum.h"
48 : #include "utils/fmgroids.h"
49 : #include "utils/guc.h"
50 : #include "utils/hsearch.h"
51 : #include "utils/inval.h"
52 : #include "utils/lsyscache.h"
53 : #include "utils/memutils.h"
54 : #include "utils/rel.h"
55 : #include "utils/rls.h"
56 : #include "utils/ruleutils.h"
57 : #include "utils/snapmgr.h"
58 : #include "utils/syscache.h"
59 :
60 : /*
61 : * Local definitions
62 : */
63 :
64 : #define RI_MAX_NUMKEYS INDEX_MAX_KEYS
65 :
66 : #define RI_INIT_CONSTRAINTHASHSIZE 64
67 : #define RI_INIT_QUERYHASHSIZE (RI_INIT_CONSTRAINTHASHSIZE * 4)
68 :
69 : #define RI_KEYS_ALL_NULL 0
70 : #define RI_KEYS_SOME_NULL 1
71 : #define RI_KEYS_NONE_NULL 2
72 :
73 : /* RI query type codes */
74 : /* these queries are executed against the PK (referenced) table: */
75 : #define RI_PLAN_CHECK_LOOKUPPK 1
76 : #define RI_PLAN_CHECK_LOOKUPPK_FROM_PK 2
77 : #define RI_PLAN_LAST_ON_PK RI_PLAN_CHECK_LOOKUPPK_FROM_PK
78 : /* these queries are executed against the FK (referencing) table: */
79 : #define RI_PLAN_CASCADE_ONDELETE 3
80 : #define RI_PLAN_CASCADE_ONUPDATE 4
81 : #define RI_PLAN_NO_ACTION 5
82 : /* For RESTRICT, the same plan can be used for both ON DELETE and ON UPDATE triggers. */
83 : #define RI_PLAN_RESTRICT 6
84 : #define RI_PLAN_SETNULL_ONDELETE 7
85 : #define RI_PLAN_SETNULL_ONUPDATE 8
86 : #define RI_PLAN_SETDEFAULT_ONDELETE 9
87 : #define RI_PLAN_SETDEFAULT_ONUPDATE 10
88 :
89 : #define MAX_QUOTED_NAME_LEN (NAMEDATALEN*2+3)
90 : #define MAX_QUOTED_REL_NAME_LEN (MAX_QUOTED_NAME_LEN*2)
91 :
92 : #define RIAttName(rel, attnum) NameStr(*attnumAttName(rel, attnum))
93 : #define RIAttType(rel, attnum) attnumTypeId(rel, attnum)
94 : #define RIAttCollation(rel, attnum) attnumCollationId(rel, attnum)
95 :
96 : #define RI_TRIGTYPE_INSERT 1
97 : #define RI_TRIGTYPE_UPDATE 2
98 : #define RI_TRIGTYPE_DELETE 3
99 :
100 : typedef struct FastPathMeta FastPathMeta;
101 :
102 : /*
103 : * RI_ConstraintInfo
104 : *
105 : * Information extracted from an FK pg_constraint entry. This is cached in
106 : * ri_constraint_cache.
107 : *
108 : * Note that pf/pp/ff_eq_oprs may hold the overlaps operator instead of equals
109 : * for the PERIOD part of a temporal foreign key.
110 : */
111 : typedef struct RI_ConstraintInfo
112 : {
113 : Oid constraint_id; /* OID of pg_constraint entry (hash key) */
114 : bool valid; /* successfully initialized? */
115 : Oid constraint_root_id; /* OID of topmost ancestor constraint;
116 : * same as constraint_id if not inherited */
117 : uint32 oidHashValue; /* hash value of constraint_id */
118 : uint32 rootHashValue; /* hash value of constraint_root_id */
119 : NameData conname; /* name of the FK constraint */
120 : Oid pk_relid; /* referenced relation */
121 : Oid fk_relid; /* referencing relation */
122 : char confupdtype; /* foreign key's ON UPDATE action */
123 : char confdeltype; /* foreign key's ON DELETE action */
124 : int ndelsetcols; /* number of columns referenced in ON DELETE
125 : * SET clause */
126 : int16 confdelsetcols[RI_MAX_NUMKEYS]; /* attnums of cols to set on
127 : * delete */
128 : char confmatchtype; /* foreign key's match type */
129 : bool hasperiod; /* if the foreign key uses PERIOD */
130 : int nkeys; /* number of key columns */
131 : int16 pk_attnums[RI_MAX_NUMKEYS]; /* attnums of referenced cols */
132 : int16 fk_attnums[RI_MAX_NUMKEYS]; /* attnums of referencing cols */
133 : Oid pf_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (PK = FK) */
134 : Oid pp_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (PK = PK) */
135 : Oid ff_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (FK = FK) */
136 : Oid period_contained_by_oper; /* anyrange <@ anyrange (or
137 : * multiranges) */
138 : Oid agged_period_contained_by_oper; /* fkattr <@ range_agg(pkattr) */
139 : Oid period_intersect_oper; /* anyrange * anyrange (or
140 : * multiranges) */
141 : dlist_node valid_link; /* Link in list of valid entries */
142 :
143 : Oid conindid;
144 : bool pk_is_partitioned;
145 :
146 : FastPathMeta *fpmeta;
147 : } RI_ConstraintInfo;
148 :
149 : typedef struct RI_CompareHashEntry RI_CompareHashEntry;
150 :
151 : /* Fast-path metadata for RI checks on foreign key referencing tables */
152 : typedef struct FastPathMeta
153 : {
154 : FmgrInfo eq_opr_finfo[RI_MAX_NUMKEYS];
155 : FmgrInfo cast_func_finfo[RI_MAX_NUMKEYS];
156 : RegProcedure regops[RI_MAX_NUMKEYS];
157 : Oid subtypes[RI_MAX_NUMKEYS];
158 : int strats[RI_MAX_NUMKEYS];
159 : } FastPathMeta;
160 :
161 : /*
162 : * RI_QueryKey
163 : *
164 : * The key identifying a prepared SPI plan in our query hashtable
165 : */
166 : typedef struct RI_QueryKey
167 : {
168 : Oid constr_id; /* OID of pg_constraint entry */
169 : int32 constr_queryno; /* query type ID, see RI_PLAN_XXX above */
170 : } RI_QueryKey;
171 :
172 : /*
173 : * RI_QueryHashEntry
174 : */
175 : typedef struct RI_QueryHashEntry
176 : {
177 : RI_QueryKey key;
178 : SPIPlanPtr plan;
179 : } RI_QueryHashEntry;
180 :
181 : /*
182 : * RI_CompareKey
183 : *
184 : * The key identifying an entry showing how to compare two values
185 : */
186 : typedef struct RI_CompareKey
187 : {
188 : Oid eq_opr; /* the equality operator to apply */
189 : Oid typeid; /* the data type to apply it to */
190 : } RI_CompareKey;
191 :
192 : /*
193 : * RI_CompareHashEntry
194 : */
195 : typedef struct RI_CompareHashEntry
196 : {
197 : RI_CompareKey key;
198 : bool valid; /* successfully initialized? */
199 : FmgrInfo eq_opr_finfo; /* call info for equality fn */
200 : FmgrInfo cast_func_finfo; /* in case we must coerce input */
201 : } RI_CompareHashEntry;
202 :
203 : /*
204 : * Maximum number of FK rows buffered before flushing.
205 : *
206 : * Larger batches amortize per-flush overhead and let the SK_SEARCHARRAY
207 : * path walk more leaf pages in a single sorted traversal. But each
208 : * buffered row is a materialized HeapTuple in flush_cxt, and the matched[]
209 : * scan in ri_FastPathFlushArray() is O(batch_size) per index match.
210 : * Benchmarking showed little difference between 16 and 64, with 256
211 : * consistently slower. 64 is a reasonable default.
212 : */
213 : #define RI_FASTPATH_BATCH_SIZE 64
214 :
215 : /*
216 : * RI_FastPathEntry
217 : * Per-constraint cache of resources needed by ri_FastPathBatchFlush().
218 : *
219 : * One entry per constraint, keyed by pg_constraint OID. Created lazily
220 : * by ri_FastPathGetEntry() on first use within a trigger-firing batch
221 : * and torn down by ri_FastPathTeardown() at batch end.
222 : *
223 : * FK tuples are buffered in batch[] across trigger invocations and
224 : * flushed when the buffer fills or the batch ends.
225 : *
226 : * RI_FastPathEntry is not subject to cache invalidation. The cached
227 : * relations are held open with locks for the transaction duration, preventing
228 : * relcache invalidation. The entry itself is torn down at batch end by
229 : * ri_FastPathEndBatch(); on abort, ResourceOwner releases the cached
230 : * relations and the XactCallback/SubXactCallback NULL the static cache pointer
231 : * to prevent any subsequent access.
232 : */
233 : typedef struct RI_FastPathEntry
234 : {
235 : Oid conoid; /* hash key: pg_constraint OID */
236 : Oid fk_relid; /* for ri_FastPathEndBatch() */
237 : Relation pk_rel;
238 : Relation idx_rel;
239 : TupleTableSlot *pk_slot;
240 : TupleTableSlot *fk_slot;
241 : MemoryContext flush_cxt; /* short-lived context for per-flush work */
242 :
243 : /*
244 : * TODO: batch[] is HeapTuple[] because the AFTER trigger machinery
245 : * currently passes tuples as HeapTuples. Once trigger infrastructure is
246 : * slotified, this should use a slot array or whatever batched tuple
247 : * storage abstraction exists at that point to be TAM-agnostic.
248 : */
249 : HeapTuple batch[RI_FASTPATH_BATCH_SIZE];
250 : int batch_count;
251 : } RI_FastPathEntry;
252 :
253 : /*
254 : * Local data
255 : */
256 : static HTAB *ri_constraint_cache = NULL;
257 : static HTAB *ri_query_cache = NULL;
258 : static HTAB *ri_compare_cache = NULL;
259 : static dclist_head ri_constraint_cache_valid_list;
260 :
261 : static HTAB *ri_fastpath_cache = NULL;
262 : static bool ri_fastpath_callback_registered = false;
263 :
264 : /*
265 : * Local function prototypes
266 : */
267 : static bool ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
268 : TupleTableSlot *oldslot,
269 : const RI_ConstraintInfo *riinfo);
270 : static Datum ri_restrict(TriggerData *trigdata, bool is_no_action);
271 : static Datum ri_set(TriggerData *trigdata, bool is_set_null, int tgkind);
272 : static void quoteOneName(char *buffer, const char *name);
273 : static void quoteRelationName(char *buffer, Relation rel);
274 : static void ri_GenerateQual(StringInfo buf,
275 : const char *sep,
276 : const char *leftop, Oid leftoptype,
277 : Oid opoid,
278 : const char *rightop, Oid rightoptype);
279 : static void ri_GenerateQualCollation(StringInfo buf, Oid collation);
280 : static int ri_NullCheck(TupleDesc tupDesc, TupleTableSlot *slot,
281 : const RI_ConstraintInfo *riinfo, bool rel_is_pk);
282 : static void ri_BuildQueryKey(RI_QueryKey *key,
283 : const RI_ConstraintInfo *riinfo,
284 : int32 constr_queryno);
285 : static bool ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot,
286 : const RI_ConstraintInfo *riinfo, bool rel_is_pk);
287 : static bool ri_CompareWithCast(Oid eq_opr, Oid typeid, Oid collid,
288 : Datum lhs, Datum rhs);
289 :
290 : static void ri_InitHashTables(void);
291 : static void InvalidateConstraintCacheCallBack(Datum arg, SysCacheIdentifier cacheid,
292 : uint32 hashvalue);
293 : static SPIPlanPtr ri_FetchPreparedPlan(RI_QueryKey *key);
294 : static void ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan);
295 : static RI_CompareHashEntry *ri_HashCompareOp(Oid eq_opr, Oid typeid);
296 :
297 : static void ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname,
298 : int tgkind);
299 : static const RI_ConstraintInfo *ri_FetchConstraintInfo(Trigger *trigger,
300 : Relation trig_rel, bool rel_is_pk);
301 : static const RI_ConstraintInfo *ri_LoadConstraintInfo(Oid constraintOid);
302 : static Oid get_ri_constraint_root(Oid constrOid);
303 : static SPIPlanPtr ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
304 : RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel);
305 : static bool ri_PerformCheck(const RI_ConstraintInfo *riinfo,
306 : RI_QueryKey *qkey, SPIPlanPtr qplan,
307 : Relation fk_rel, Relation pk_rel,
308 : TupleTableSlot *oldslot, TupleTableSlot *newslot,
309 : bool is_restrict,
310 : bool detectNewRows, int expect_OK);
311 : static void ri_FastPathCheck(const RI_ConstraintInfo *riinfo,
312 : Relation fk_rel, TupleTableSlot *newslot);
313 : static void ri_FastPathBatchAdd(const RI_ConstraintInfo *riinfo,
314 : Relation fk_rel, TupleTableSlot *newslot);
315 : static void ri_FastPathBatchFlush(RI_FastPathEntry *fpentry, Relation fk_rel,
316 : const RI_ConstraintInfo *riinfo);
317 : static int ri_FastPathFlushArray(RI_FastPathEntry *fpentry, TupleTableSlot *fk_slot,
318 : const RI_ConstraintInfo *riinfo, Relation fk_rel,
319 : Snapshot snapshot, IndexScanDesc scandesc);
320 : static int ri_FastPathFlushLoop(RI_FastPathEntry *fpentry, TupleTableSlot *fk_slot,
321 : const RI_ConstraintInfo *riinfo, Relation fk_rel,
322 : Snapshot snapshot, IndexScanDesc scandesc);
323 : static bool ri_FastPathProbeOne(Relation pk_rel, Relation idx_rel,
324 : IndexScanDesc scandesc, TupleTableSlot *slot,
325 : Snapshot snapshot, const RI_ConstraintInfo *riinfo,
326 : ScanKeyData *skey, int nkeys);
327 : static bool ri_LockPKTuple(Relation pk_rel, TupleTableSlot *slot, Snapshot snap,
328 : bool *concurrently_updated);
329 : static bool ri_fastpath_is_applicable(const RI_ConstraintInfo *riinfo);
330 : static void ri_CheckPermissions(Relation query_rel);
331 : static bool recheck_matched_pk_tuple(Relation idxrel, ScanKeyData *skeys,
332 : TupleTableSlot *new_slot);
333 : static void build_index_scankeys(const RI_ConstraintInfo *riinfo,
334 : Relation idx_rel, Datum *pk_vals,
335 : char *pk_nulls, ScanKey skeys);
336 : static void ri_populate_fastpath_metadata(RI_ConstraintInfo *riinfo,
337 : Relation fk_rel, Relation idx_rel);
338 : static void ri_ExtractValues(Relation rel, TupleTableSlot *slot,
339 : const RI_ConstraintInfo *riinfo, bool rel_is_pk,
340 : Datum *vals, char *nulls);
341 : pg_noreturn static void ri_ReportViolation(const RI_ConstraintInfo *riinfo,
342 : Relation pk_rel, Relation fk_rel,
343 : TupleTableSlot *violatorslot, TupleDesc tupdesc,
344 : int queryno, bool is_restrict, bool partgone);
345 : static RI_FastPathEntry *ri_FastPathGetEntry(const RI_ConstraintInfo *riinfo,
346 : Relation fk_rel);
347 : static void ri_FastPathEndBatch(void *arg);
348 : static void ri_FastPathTeardown(void);
349 :
350 :
351 : /*
352 : * RI_FKey_check -
353 : *
354 : * Check foreign key existence (combined for INSERT and UPDATE).
355 : */
356 : static Datum
357 604706 : RI_FKey_check(TriggerData *trigdata)
358 : {
359 : const RI_ConstraintInfo *riinfo;
360 : Relation fk_rel;
361 : Relation pk_rel;
362 : TupleTableSlot *newslot;
363 : RI_QueryKey qkey;
364 : SPIPlanPtr qplan;
365 :
366 604706 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
367 : trigdata->tg_relation, false);
368 :
369 604706 : if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
370 294 : newslot = trigdata->tg_newslot;
371 : else
372 604412 : newslot = trigdata->tg_trigslot;
373 :
374 : /*
375 : * We should not even consider checking the row if it is no longer valid,
376 : * since it was either deleted (so the deferred check should be skipped)
377 : * or updated (in which case only the latest version of the row should be
378 : * checked). Test its liveness according to SnapshotSelf. We need pin
379 : * and lock on the buffer to call HeapTupleSatisfiesVisibility. Caller
380 : * should be holding pin, but not lock.
381 : */
382 604706 : if (!table_tuple_satisfies_snapshot(trigdata->tg_relation, newslot, SnapshotSelf))
383 40 : return PointerGetDatum(NULL);
384 :
385 604666 : fk_rel = trigdata->tg_relation;
386 :
387 604666 : switch (ri_NullCheck(RelationGetDescr(fk_rel), newslot, riinfo, false))
388 : {
389 98 : case RI_KEYS_ALL_NULL:
390 :
391 : /*
392 : * No further check needed - an all-NULL key passes every type of
393 : * foreign key constraint.
394 : */
395 98 : return PointerGetDatum(NULL);
396 :
397 104 : case RI_KEYS_SOME_NULL:
398 :
399 : /*
400 : * This is the only case that differs between the three kinds of
401 : * MATCH.
402 : */
403 104 : switch (riinfo->confmatchtype)
404 : {
405 24 : case FKCONSTR_MATCH_FULL:
406 :
407 : /*
408 : * Not allowed - MATCH FULL says either all or none of the
409 : * attributes can be NULLs
410 : */
411 24 : ereport(ERROR,
412 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
413 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
414 : RelationGetRelationName(fk_rel),
415 : NameStr(riinfo->conname)),
416 : errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
417 : errtableconstraint(fk_rel,
418 : NameStr(riinfo->conname))));
419 : return PointerGetDatum(NULL);
420 :
421 80 : case FKCONSTR_MATCH_SIMPLE:
422 :
423 : /*
424 : * MATCH SIMPLE - if ANY column is null, the key passes
425 : * the constraint.
426 : */
427 80 : return PointerGetDatum(NULL);
428 :
429 : #ifdef NOT_USED
430 : case FKCONSTR_MATCH_PARTIAL:
431 :
432 : /*
433 : * MATCH PARTIAL - all non-null columns must match. (not
434 : * implemented, can be done by modifying the query below
435 : * to only include non-null columns, or by writing a
436 : * special version here)
437 : */
438 : break;
439 : #endif
440 : }
441 :
442 : case RI_KEYS_NONE_NULL:
443 :
444 : /*
445 : * Have a full qualified key - continue below for all three kinds
446 : * of MATCH.
447 : */
448 604464 : break;
449 : }
450 :
451 : /*
452 : * Fast path: probe the PK unique index directly, bypassing SPI.
453 : *
454 : * For non-partitioned, non-temporal FKs, we can skip the SPI machinery
455 : * (plan cache, executor setup, etc.) and do a direct index scan + tuple
456 : * lock. This is semantically equivalent to the SPI path below but avoids
457 : * the per-row executor overhead.
458 : *
459 : * ri_FastPathBatchAdd() and ri_FastPathCheck() report the violation
460 : * themselves if no matching PK row is found, so they only return on
461 : * success.
462 : */
463 604464 : if (ri_fastpath_is_applicable(riinfo))
464 : {
465 603674 : if (AfterTriggerIsActive())
466 : {
467 : /* Batched path: buffer and probe in groups */
468 603630 : ri_FastPathBatchAdd(riinfo, fk_rel, newslot);
469 : }
470 : else
471 : {
472 : /* ALTER TABLE validation: per-row, no cache */
473 44 : ri_FastPathCheck(riinfo, fk_rel, newslot);
474 : }
475 603670 : return PointerGetDatum(NULL);
476 : }
477 :
478 790 : SPI_connect();
479 :
480 : /*
481 : * pk_rel is opened in RowShareLock mode since that's what our eventual
482 : * SELECT FOR KEY SHARE will get on it.
483 : */
484 790 : pk_rel = table_open(riinfo->pk_relid, RowShareLock);
485 :
486 : /* Fetch or prepare a saved plan for the real check */
487 790 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK);
488 :
489 790 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
490 : {
491 : StringInfoData querybuf;
492 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
493 : char attname[MAX_QUOTED_NAME_LEN];
494 : char paramname[16];
495 : const char *querysep;
496 : Oid queryoids[RI_MAX_NUMKEYS];
497 : const char *pk_only;
498 :
499 : /* ----------
500 : * The query string built is
501 : * SELECT 1 FROM [ONLY] <pktable> x WHERE pkatt1 = $1 [AND ...]
502 : * FOR KEY SHARE OF x
503 : * The type id's for the $ parameters are those of the
504 : * corresponding FK attributes.
505 : *
506 : * But for temporal FKs we need to make sure
507 : * the FK's range is completely covered.
508 : * So we use this query instead:
509 : * SELECT 1
510 : * FROM (
511 : * SELECT pkperiodatt AS r
512 : * FROM [ONLY] pktable x
513 : * WHERE pkatt1 = $1 [AND ...]
514 : * AND pkperiodatt && $n
515 : * FOR KEY SHARE OF x
516 : * ) x1
517 : * HAVING $n <@ range_agg(x1.r)
518 : * Note if FOR KEY SHARE ever allows GROUP BY and HAVING
519 : * we can make this a bit simpler.
520 : * ----------
521 : */
522 370 : initStringInfo(&querybuf);
523 740 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
524 370 : "" : "ONLY ";
525 370 : quoteRelationName(pkrelname, pk_rel);
526 370 : if (riinfo->hasperiod)
527 : {
528 68 : quoteOneName(attname,
529 68 : RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
530 :
531 68 : appendStringInfo(&querybuf,
532 : "SELECT 1 FROM (SELECT %s AS r FROM %s%s x",
533 : attname, pk_only, pkrelname);
534 : }
535 : else
536 : {
537 302 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
538 : pk_only, pkrelname);
539 : }
540 370 : querysep = "WHERE";
541 824 : for (int i = 0; i < riinfo->nkeys; i++)
542 : {
543 454 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
544 454 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
545 :
546 454 : quoteOneName(attname,
547 454 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
548 454 : sprintf(paramname, "$%d", i + 1);
549 454 : ri_GenerateQual(&querybuf, querysep,
550 : attname, pk_type,
551 454 : riinfo->pf_eq_oprs[i],
552 : paramname, fk_type);
553 454 : querysep = "AND";
554 454 : queryoids[i] = fk_type;
555 : }
556 370 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
557 370 : if (riinfo->hasperiod)
558 : {
559 68 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
560 :
561 68 : appendStringInfoString(&querybuf, ") x1 HAVING ");
562 68 : sprintf(paramname, "$%d", riinfo->nkeys);
563 68 : ri_GenerateQual(&querybuf, "",
564 : paramname, fk_type,
565 68 : riinfo->agged_period_contained_by_oper,
566 : "pg_catalog.range_agg", ANYMULTIRANGEOID);
567 68 : appendStringInfoString(&querybuf, "(x1.r)");
568 : }
569 :
570 : /* Prepare and save the plan */
571 370 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
572 : &qkey, fk_rel, pk_rel);
573 : }
574 :
575 : /*
576 : * Now check that foreign key exists in PK table
577 : *
578 : * XXX detectNewRows must be true when a partitioned table is on the
579 : * referenced side. The reason is that our snapshot must be fresh in
580 : * order for the hack in find_inheritance_children() to work.
581 : */
582 790 : ri_PerformCheck(riinfo, &qkey, qplan,
583 : fk_rel, pk_rel,
584 : NULL, newslot,
585 : false,
586 790 : pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE,
587 : SPI_OK_SELECT);
588 :
589 650 : if (SPI_finish() != SPI_OK_FINISH)
590 0 : elog(ERROR, "SPI_finish failed");
591 :
592 650 : table_close(pk_rel, RowShareLock);
593 :
594 650 : return PointerGetDatum(NULL);
595 : }
596 :
597 :
598 : /*
599 : * RI_FKey_check_ins -
600 : *
601 : * Check foreign key existence at insert event on FK table.
602 : */
603 : Datum
604 604412 : RI_FKey_check_ins(PG_FUNCTION_ARGS)
605 : {
606 : /* Check that this is a valid trigger call on the right time and event. */
607 604412 : ri_CheckTrigger(fcinfo, "RI_FKey_check_ins", RI_TRIGTYPE_INSERT);
608 :
609 : /* Share code with UPDATE case. */
610 604412 : return RI_FKey_check((TriggerData *) fcinfo->context);
611 : }
612 :
613 :
614 : /*
615 : * RI_FKey_check_upd -
616 : *
617 : * Check foreign key existence at update event on FK table.
618 : */
619 : Datum
620 294 : RI_FKey_check_upd(PG_FUNCTION_ARGS)
621 : {
622 : /* Check that this is a valid trigger call on the right time and event. */
623 294 : ri_CheckTrigger(fcinfo, "RI_FKey_check_upd", RI_TRIGTYPE_UPDATE);
624 :
625 : /* Share code with INSERT case. */
626 294 : return RI_FKey_check((TriggerData *) fcinfo->context);
627 : }
628 :
629 :
630 : /*
631 : * ri_Check_Pk_Match
632 : *
633 : * Check to see if another PK row has been created that provides the same
634 : * key values as the "oldslot" that's been modified or deleted in our trigger
635 : * event. Returns true if a match is found in the PK table.
636 : *
637 : * We assume the caller checked that the oldslot contains no NULL key values,
638 : * since otherwise a match is impossible.
639 : */
640 : static bool
641 522 : ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
642 : TupleTableSlot *oldslot,
643 : const RI_ConstraintInfo *riinfo)
644 : {
645 : SPIPlanPtr qplan;
646 : RI_QueryKey qkey;
647 : bool result;
648 :
649 : /* Only called for non-null rows */
650 : Assert(ri_NullCheck(RelationGetDescr(pk_rel), oldslot, riinfo, true) == RI_KEYS_NONE_NULL);
651 :
652 522 : SPI_connect();
653 :
654 : /*
655 : * Fetch or prepare a saved plan for checking PK table with values coming
656 : * from a PK row
657 : */
658 522 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK_FROM_PK);
659 :
660 522 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
661 : {
662 : StringInfoData querybuf;
663 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
664 : char attname[MAX_QUOTED_NAME_LEN];
665 : char paramname[16];
666 : const char *querysep;
667 : const char *pk_only;
668 : Oid queryoids[RI_MAX_NUMKEYS];
669 :
670 : /* ----------
671 : * The query string built is
672 : * SELECT 1 FROM [ONLY] <pktable> x WHERE pkatt1 = $1 [AND ...]
673 : * FOR KEY SHARE OF x
674 : * The type id's for the $ parameters are those of the
675 : * PK attributes themselves.
676 : *
677 : * But for temporal FKs we need to make sure
678 : * the old PK's range is completely covered.
679 : * So we use this query instead:
680 : * SELECT 1
681 : * FROM (
682 : * SELECT pkperiodatt AS r
683 : * FROM [ONLY] pktable x
684 : * WHERE pkatt1 = $1 [AND ...]
685 : * AND pkperiodatt && $n
686 : * FOR KEY SHARE OF x
687 : * ) x1
688 : * HAVING $n <@ range_agg(x1.r)
689 : * Note if FOR KEY SHARE ever allows GROUP BY and HAVING
690 : * we can make this a bit simpler.
691 : * ----------
692 : */
693 244 : initStringInfo(&querybuf);
694 488 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
695 244 : "" : "ONLY ";
696 244 : quoteRelationName(pkrelname, pk_rel);
697 244 : if (riinfo->hasperiod)
698 : {
699 0 : quoteOneName(attname, RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
700 :
701 0 : appendStringInfo(&querybuf,
702 : "SELECT 1 FROM (SELECT %s AS r FROM %s%s x",
703 : attname, pk_only, pkrelname);
704 : }
705 : else
706 : {
707 244 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
708 : pk_only, pkrelname);
709 : }
710 244 : querysep = "WHERE";
711 561 : for (int i = 0; i < riinfo->nkeys; i++)
712 : {
713 317 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
714 :
715 317 : quoteOneName(attname,
716 317 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
717 317 : sprintf(paramname, "$%d", i + 1);
718 317 : ri_GenerateQual(&querybuf, querysep,
719 : attname, pk_type,
720 317 : riinfo->pp_eq_oprs[i],
721 : paramname, pk_type);
722 317 : querysep = "AND";
723 317 : queryoids[i] = pk_type;
724 : }
725 244 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
726 244 : if (riinfo->hasperiod)
727 : {
728 0 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
729 :
730 0 : appendStringInfoString(&querybuf, ") x1 HAVING ");
731 0 : sprintf(paramname, "$%d", riinfo->nkeys);
732 0 : ri_GenerateQual(&querybuf, "",
733 : paramname, fk_type,
734 0 : riinfo->agged_period_contained_by_oper,
735 : "pg_catalog.range_agg", ANYMULTIRANGEOID);
736 0 : appendStringInfoString(&querybuf, "(x1.r)");
737 : }
738 :
739 : /* Prepare and save the plan */
740 244 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
741 : &qkey, fk_rel, pk_rel);
742 : }
743 :
744 : /*
745 : * We have a plan now. Run it.
746 : */
747 522 : result = ri_PerformCheck(riinfo, &qkey, qplan,
748 : fk_rel, pk_rel,
749 : oldslot, NULL,
750 : false,
751 : true, /* treat like update */
752 : SPI_OK_SELECT);
753 :
754 522 : if (SPI_finish() != SPI_OK_FINISH)
755 0 : elog(ERROR, "SPI_finish failed");
756 :
757 522 : return result;
758 : }
759 :
760 :
761 : /*
762 : * RI_FKey_noaction_del -
763 : *
764 : * Give an error and roll back the current transaction if the
765 : * delete has resulted in a violation of the given referential
766 : * integrity constraint.
767 : */
768 : Datum
769 312 : RI_FKey_noaction_del(PG_FUNCTION_ARGS)
770 : {
771 : /* Check that this is a valid trigger call on the right time and event. */
772 312 : ri_CheckTrigger(fcinfo, "RI_FKey_noaction_del", RI_TRIGTYPE_DELETE);
773 :
774 : /* Share code with RESTRICT/UPDATE cases. */
775 312 : return ri_restrict((TriggerData *) fcinfo->context, true);
776 : }
777 :
778 : /*
779 : * RI_FKey_restrict_del -
780 : *
781 : * Restrict delete from PK table to rows unreferenced by foreign key.
782 : *
783 : * The SQL standard intends that this referential action occur exactly when
784 : * the delete is performed, rather than after. This appears to be
785 : * the only difference between "NO ACTION" and "RESTRICT". In Postgres
786 : * we still implement this as an AFTER trigger, but it's non-deferrable.
787 : */
788 : Datum
789 8 : RI_FKey_restrict_del(PG_FUNCTION_ARGS)
790 : {
791 : /* Check that this is a valid trigger call on the right time and event. */
792 8 : ri_CheckTrigger(fcinfo, "RI_FKey_restrict_del", RI_TRIGTYPE_DELETE);
793 :
794 : /* Share code with NO ACTION/UPDATE cases. */
795 8 : return ri_restrict((TriggerData *) fcinfo->context, false);
796 : }
797 :
798 : /*
799 : * RI_FKey_noaction_upd -
800 : *
801 : * Give an error and roll back the current transaction if the
802 : * update has resulted in a violation of the given referential
803 : * integrity constraint.
804 : */
805 : Datum
806 356 : RI_FKey_noaction_upd(PG_FUNCTION_ARGS)
807 : {
808 : /* Check that this is a valid trigger call on the right time and event. */
809 356 : ri_CheckTrigger(fcinfo, "RI_FKey_noaction_upd", RI_TRIGTYPE_UPDATE);
810 :
811 : /* Share code with RESTRICT/DELETE cases. */
812 356 : return ri_restrict((TriggerData *) fcinfo->context, true);
813 : }
814 :
815 : /*
816 : * RI_FKey_restrict_upd -
817 : *
818 : * Restrict update of PK to rows unreferenced by foreign key.
819 : *
820 : * The SQL standard intends that this referential action occur exactly when
821 : * the update is performed, rather than after. This appears to be
822 : * the only difference between "NO ACTION" and "RESTRICT". In Postgres
823 : * we still implement this as an AFTER trigger, but it's non-deferrable.
824 : */
825 : Datum
826 20 : RI_FKey_restrict_upd(PG_FUNCTION_ARGS)
827 : {
828 : /* Check that this is a valid trigger call on the right time and event. */
829 20 : ri_CheckTrigger(fcinfo, "RI_FKey_restrict_upd", RI_TRIGTYPE_UPDATE);
830 :
831 : /* Share code with NO ACTION/DELETE cases. */
832 20 : return ri_restrict((TriggerData *) fcinfo->context, false);
833 : }
834 :
835 : /*
836 : * ri_restrict -
837 : *
838 : * Common code for ON DELETE RESTRICT, ON DELETE NO ACTION,
839 : * ON UPDATE RESTRICT, and ON UPDATE NO ACTION.
840 : */
841 : static Datum
842 784 : ri_restrict(TriggerData *trigdata, bool is_no_action)
843 : {
844 : const RI_ConstraintInfo *riinfo;
845 : Relation fk_rel;
846 : Relation pk_rel;
847 : TupleTableSlot *oldslot;
848 : RI_QueryKey qkey;
849 : SPIPlanPtr qplan;
850 :
851 784 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
852 : trigdata->tg_relation, true);
853 :
854 : /*
855 : * Get the relation descriptors of the FK and PK tables and the old tuple.
856 : *
857 : * fk_rel is opened in RowShareLock mode since that's what our eventual
858 : * SELECT FOR KEY SHARE will get on it.
859 : */
860 784 : fk_rel = table_open(riinfo->fk_relid, RowShareLock);
861 784 : pk_rel = trigdata->tg_relation;
862 784 : oldslot = trigdata->tg_trigslot;
863 :
864 : /*
865 : * If another PK row now exists providing the old key values, we should
866 : * not do anything. However, this check should only be made in the NO
867 : * ACTION case; in RESTRICT cases we don't wish to allow another row to be
868 : * substituted.
869 : *
870 : * If the foreign key has PERIOD, we incorporate looking for replacement
871 : * rows in the main SQL query below, so we needn't do it here.
872 : */
873 1306 : if (is_no_action && !riinfo->hasperiod &&
874 522 : ri_Check_Pk_Match(pk_rel, fk_rel, oldslot, riinfo))
875 : {
876 38 : table_close(fk_rel, RowShareLock);
877 38 : return PointerGetDatum(NULL);
878 : }
879 :
880 746 : SPI_connect();
881 :
882 : /*
883 : * Fetch or prepare a saved plan for the restrict lookup (it's the same
884 : * query for delete and update cases)
885 : */
886 746 : ri_BuildQueryKey(&qkey, riinfo, is_no_action ? RI_PLAN_NO_ACTION : RI_PLAN_RESTRICT);
887 :
888 746 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
889 : {
890 : StringInfoData querybuf;
891 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
892 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
893 : char attname[MAX_QUOTED_NAME_LEN];
894 : char periodattname[MAX_QUOTED_NAME_LEN];
895 : char paramname[16];
896 : const char *querysep;
897 : Oid queryoids[RI_MAX_NUMKEYS];
898 : const char *fk_only;
899 :
900 : /* ----------
901 : * The query string built is
902 : * SELECT 1 FROM [ONLY] <fktable> x WHERE $1 = fkatt1 [AND ...]
903 : * FOR KEY SHARE OF x
904 : * The type id's for the $ parameters are those of the
905 : * corresponding PK attributes.
906 : * ----------
907 : */
908 307 : initStringInfo(&querybuf);
909 614 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
910 307 : "" : "ONLY ";
911 307 : quoteRelationName(fkrelname, fk_rel);
912 307 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
913 : fk_only, fkrelname);
914 307 : querysep = "WHERE";
915 777 : for (int i = 0; i < riinfo->nkeys; i++)
916 : {
917 470 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
918 470 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
919 :
920 470 : quoteOneName(attname,
921 470 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
922 470 : sprintf(paramname, "$%d", i + 1);
923 470 : ri_GenerateQual(&querybuf, querysep,
924 : paramname, pk_type,
925 470 : riinfo->pf_eq_oprs[i],
926 : attname, fk_type);
927 470 : querysep = "AND";
928 470 : queryoids[i] = pk_type;
929 : }
930 :
931 : /*----------
932 : * For temporal foreign keys, a reference could still be valid if the
933 : * referenced range didn't change too much. Also if a referencing
934 : * range extends past the current PK row, we don't want to check that
935 : * part: some other PK row should fulfill it. We only want to check
936 : * the part matching the PK record we've changed. Therefore to find
937 : * invalid records we do this:
938 : *
939 : * SELECT 1 FROM [ONLY] <fktable> x WHERE $1 = x.fkatt1 [AND ...]
940 : * -- begin temporal
941 : * AND $n && x.fkperiod
942 : * AND NOT coalesce((x.fkperiod * $n) <@
943 : * (SELECT range_agg(r)
944 : * FROM (SELECT y.pkperiod r
945 : * FROM [ONLY] <pktable> y
946 : * WHERE $1 = y.pkatt1 [AND ...] AND $n && y.pkperiod
947 : * FOR KEY SHARE OF y) y2), false)
948 : * -- end temporal
949 : * FOR KEY SHARE OF x
950 : *
951 : * We need the coalesce in case the first subquery returns no rows.
952 : * We need the second subquery because FOR KEY SHARE doesn't support
953 : * aggregate queries.
954 : */
955 307 : if (riinfo->hasperiod && is_no_action)
956 : {
957 90 : Oid pk_period_type = RIAttType(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]);
958 90 : Oid fk_period_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
959 : StringInfoData intersectbuf;
960 : StringInfoData replacementsbuf;
961 180 : char *pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
962 90 : "" : "ONLY ";
963 :
964 90 : quoteOneName(attname, RIAttName(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]));
965 90 : sprintf(paramname, "$%d", riinfo->nkeys);
966 :
967 90 : appendStringInfoString(&querybuf, " AND NOT coalesce(");
968 :
969 : /* Intersect the fk with the old pk range */
970 90 : initStringInfo(&intersectbuf);
971 90 : appendStringInfoChar(&intersectbuf, '(');
972 90 : ri_GenerateQual(&intersectbuf, "",
973 : attname, fk_period_type,
974 90 : riinfo->period_intersect_oper,
975 : paramname, pk_period_type);
976 90 : appendStringInfoChar(&intersectbuf, ')');
977 :
978 : /* Find the remaining history */
979 90 : initStringInfo(&replacementsbuf);
980 90 : appendStringInfoString(&replacementsbuf, "(SELECT pg_catalog.range_agg(r) FROM ");
981 :
982 90 : quoteOneName(periodattname, RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
983 90 : quoteRelationName(pkrelname, pk_rel);
984 90 : appendStringInfo(&replacementsbuf, "(SELECT y.%s r FROM %s%s y",
985 : periodattname, pk_only, pkrelname);
986 :
987 : /* Restrict pk rows to what matches */
988 90 : querysep = "WHERE";
989 270 : for (int i = 0; i < riinfo->nkeys; i++)
990 : {
991 180 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
992 :
993 180 : quoteOneName(attname,
994 180 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
995 180 : sprintf(paramname, "$%d", i + 1);
996 180 : ri_GenerateQual(&replacementsbuf, querysep,
997 : paramname, pk_type,
998 180 : riinfo->pp_eq_oprs[i],
999 : attname, pk_type);
1000 180 : querysep = "AND";
1001 180 : queryoids[i] = pk_type;
1002 : }
1003 90 : appendStringInfoString(&replacementsbuf, " FOR KEY SHARE OF y) y2)");
1004 :
1005 90 : ri_GenerateQual(&querybuf, "",
1006 90 : intersectbuf.data, fk_period_type,
1007 90 : riinfo->agged_period_contained_by_oper,
1008 90 : replacementsbuf.data, ANYMULTIRANGEOID);
1009 : /* end of coalesce: */
1010 90 : appendStringInfoString(&querybuf, ", false)");
1011 : }
1012 :
1013 307 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
1014 :
1015 : /* Prepare and save the plan */
1016 307 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
1017 : &qkey, fk_rel, pk_rel);
1018 : }
1019 :
1020 : /*
1021 : * We have a plan now. Run it to check for existing references.
1022 : */
1023 746 : ri_PerformCheck(riinfo, &qkey, qplan,
1024 : fk_rel, pk_rel,
1025 : oldslot, NULL,
1026 : !is_no_action,
1027 : true, /* must detect new rows */
1028 746 : SPI_OK_SELECT);
1029 :
1030 416 : if (SPI_finish() != SPI_OK_FINISH)
1031 0 : elog(ERROR, "SPI_finish failed");
1032 :
1033 416 : table_close(fk_rel, RowShareLock);
1034 :
1035 416 : return PointerGetDatum(NULL);
1036 : }
1037 :
1038 :
1039 : /*
1040 : * RI_FKey_cascade_del -
1041 : *
1042 : * Cascaded delete foreign key references at delete event on PK table.
1043 : */
1044 : Datum
1045 98 : RI_FKey_cascade_del(PG_FUNCTION_ARGS)
1046 : {
1047 98 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
1048 : const RI_ConstraintInfo *riinfo;
1049 : Relation fk_rel;
1050 : Relation pk_rel;
1051 : TupleTableSlot *oldslot;
1052 : RI_QueryKey qkey;
1053 : SPIPlanPtr qplan;
1054 :
1055 : /* Check that this is a valid trigger call on the right time and event. */
1056 98 : ri_CheckTrigger(fcinfo, "RI_FKey_cascade_del", RI_TRIGTYPE_DELETE);
1057 :
1058 98 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
1059 : trigdata->tg_relation, true);
1060 :
1061 : /*
1062 : * Get the relation descriptors of the FK and PK tables and the old tuple.
1063 : *
1064 : * fk_rel is opened in RowExclusiveLock mode since that's what our
1065 : * eventual DELETE will get on it.
1066 : */
1067 98 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
1068 98 : pk_rel = trigdata->tg_relation;
1069 98 : oldslot = trigdata->tg_trigslot;
1070 :
1071 98 : SPI_connect();
1072 :
1073 : /* Fetch or prepare a saved plan for the cascaded delete */
1074 98 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_ONDELETE);
1075 :
1076 98 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
1077 : {
1078 : StringInfoData querybuf;
1079 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1080 : char attname[MAX_QUOTED_NAME_LEN];
1081 : char paramname[16];
1082 : const char *querysep;
1083 : Oid queryoids[RI_MAX_NUMKEYS];
1084 : const char *fk_only;
1085 :
1086 : /* ----------
1087 : * The query string built is
1088 : * DELETE FROM [ONLY] <fktable> WHERE $1 = fkatt1 [AND ...]
1089 : * The type id's for the $ parameters are those of the
1090 : * corresponding PK attributes.
1091 : * ----------
1092 : */
1093 58 : initStringInfo(&querybuf);
1094 116 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1095 58 : "" : "ONLY ";
1096 58 : quoteRelationName(fkrelname, fk_rel);
1097 58 : appendStringInfo(&querybuf, "DELETE FROM %s%s",
1098 : fk_only, fkrelname);
1099 58 : querysep = "WHERE";
1100 128 : for (int i = 0; i < riinfo->nkeys; i++)
1101 : {
1102 70 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1103 70 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1104 :
1105 70 : quoteOneName(attname,
1106 70 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1107 70 : sprintf(paramname, "$%d", i + 1);
1108 70 : ri_GenerateQual(&querybuf, querysep,
1109 : paramname, pk_type,
1110 70 : riinfo->pf_eq_oprs[i],
1111 : attname, fk_type);
1112 70 : querysep = "AND";
1113 70 : queryoids[i] = pk_type;
1114 : }
1115 :
1116 : /* Prepare and save the plan */
1117 58 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
1118 : &qkey, fk_rel, pk_rel);
1119 : }
1120 :
1121 : /*
1122 : * We have a plan now. Build up the arguments from the key values in the
1123 : * deleted PK tuple and delete the referencing rows
1124 : */
1125 98 : ri_PerformCheck(riinfo, &qkey, qplan,
1126 : fk_rel, pk_rel,
1127 : oldslot, NULL,
1128 : false,
1129 : true, /* must detect new rows */
1130 : SPI_OK_DELETE);
1131 :
1132 97 : if (SPI_finish() != SPI_OK_FINISH)
1133 0 : elog(ERROR, "SPI_finish failed");
1134 :
1135 97 : table_close(fk_rel, RowExclusiveLock);
1136 :
1137 97 : return PointerGetDatum(NULL);
1138 : }
1139 :
1140 :
1141 : /*
1142 : * RI_FKey_cascade_upd -
1143 : *
1144 : * Cascaded update foreign key references at update event on PK table.
1145 : */
1146 : Datum
1147 144 : RI_FKey_cascade_upd(PG_FUNCTION_ARGS)
1148 : {
1149 144 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
1150 : const RI_ConstraintInfo *riinfo;
1151 : Relation fk_rel;
1152 : Relation pk_rel;
1153 : TupleTableSlot *newslot;
1154 : TupleTableSlot *oldslot;
1155 : RI_QueryKey qkey;
1156 : SPIPlanPtr qplan;
1157 :
1158 : /* Check that this is a valid trigger call on the right time and event. */
1159 144 : ri_CheckTrigger(fcinfo, "RI_FKey_cascade_upd", RI_TRIGTYPE_UPDATE);
1160 :
1161 144 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
1162 : trigdata->tg_relation, true);
1163 :
1164 : /*
1165 : * Get the relation descriptors of the FK and PK tables and the new and
1166 : * old tuple.
1167 : *
1168 : * fk_rel is opened in RowExclusiveLock mode since that's what our
1169 : * eventual UPDATE will get on it.
1170 : */
1171 144 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
1172 144 : pk_rel = trigdata->tg_relation;
1173 144 : newslot = trigdata->tg_newslot;
1174 144 : oldslot = trigdata->tg_trigslot;
1175 :
1176 144 : SPI_connect();
1177 :
1178 : /* Fetch or prepare a saved plan for the cascaded update */
1179 144 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_ONUPDATE);
1180 :
1181 144 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
1182 : {
1183 : StringInfoData querybuf;
1184 : StringInfoData qualbuf;
1185 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1186 : char attname[MAX_QUOTED_NAME_LEN];
1187 : char paramname[16];
1188 : const char *querysep;
1189 : const char *qualsep;
1190 : Oid queryoids[RI_MAX_NUMKEYS * 2];
1191 : const char *fk_only;
1192 :
1193 : /* ----------
1194 : * The query string built is
1195 : * UPDATE [ONLY] <fktable> SET fkatt1 = $1 [, ...]
1196 : * WHERE $n = fkatt1 [AND ...]
1197 : * The type id's for the $ parameters are those of the
1198 : * corresponding PK attributes. Note that we are assuming
1199 : * there is an assignment cast from the PK to the FK type;
1200 : * else the parser will fail.
1201 : * ----------
1202 : */
1203 84 : initStringInfo(&querybuf);
1204 84 : initStringInfo(&qualbuf);
1205 168 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1206 84 : "" : "ONLY ";
1207 84 : quoteRelationName(fkrelname, fk_rel);
1208 84 : appendStringInfo(&querybuf, "UPDATE %s%s SET",
1209 : fk_only, fkrelname);
1210 84 : querysep = "";
1211 84 : qualsep = "WHERE";
1212 184 : for (int i = 0, j = riinfo->nkeys; i < riinfo->nkeys; i++, j++)
1213 : {
1214 100 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1215 100 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1216 :
1217 100 : quoteOneName(attname,
1218 100 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1219 100 : appendStringInfo(&querybuf,
1220 : "%s %s = $%d",
1221 : querysep, attname, i + 1);
1222 100 : sprintf(paramname, "$%d", j + 1);
1223 100 : ri_GenerateQual(&qualbuf, qualsep,
1224 : paramname, pk_type,
1225 100 : riinfo->pf_eq_oprs[i],
1226 : attname, fk_type);
1227 100 : querysep = ",";
1228 100 : qualsep = "AND";
1229 100 : queryoids[i] = pk_type;
1230 100 : queryoids[j] = pk_type;
1231 : }
1232 84 : appendBinaryStringInfo(&querybuf, qualbuf.data, qualbuf.len);
1233 :
1234 : /* Prepare and save the plan */
1235 84 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys * 2, queryoids,
1236 : &qkey, fk_rel, pk_rel);
1237 : }
1238 :
1239 : /*
1240 : * We have a plan now. Run it to update the existing references.
1241 : */
1242 144 : ri_PerformCheck(riinfo, &qkey, qplan,
1243 : fk_rel, pk_rel,
1244 : oldslot, newslot,
1245 : false,
1246 : true, /* must detect new rows */
1247 : SPI_OK_UPDATE);
1248 :
1249 144 : if (SPI_finish() != SPI_OK_FINISH)
1250 0 : elog(ERROR, "SPI_finish failed");
1251 :
1252 144 : table_close(fk_rel, RowExclusiveLock);
1253 :
1254 144 : return PointerGetDatum(NULL);
1255 : }
1256 :
1257 :
1258 : /*
1259 : * RI_FKey_setnull_del -
1260 : *
1261 : * Set foreign key references to NULL values at delete event on PK table.
1262 : */
1263 : Datum
1264 65 : RI_FKey_setnull_del(PG_FUNCTION_ARGS)
1265 : {
1266 : /* Check that this is a valid trigger call on the right time and event. */
1267 65 : ri_CheckTrigger(fcinfo, "RI_FKey_setnull_del", RI_TRIGTYPE_DELETE);
1268 :
1269 : /* Share code with UPDATE case */
1270 65 : return ri_set((TriggerData *) fcinfo->context, true, RI_TRIGTYPE_DELETE);
1271 : }
1272 :
1273 : /*
1274 : * RI_FKey_setnull_upd -
1275 : *
1276 : * Set foreign key references to NULL at update event on PK table.
1277 : */
1278 : Datum
1279 20 : RI_FKey_setnull_upd(PG_FUNCTION_ARGS)
1280 : {
1281 : /* Check that this is a valid trigger call on the right time and event. */
1282 20 : ri_CheckTrigger(fcinfo, "RI_FKey_setnull_upd", RI_TRIGTYPE_UPDATE);
1283 :
1284 : /* Share code with DELETE case */
1285 20 : return ri_set((TriggerData *) fcinfo->context, true, RI_TRIGTYPE_UPDATE);
1286 : }
1287 :
1288 : /*
1289 : * RI_FKey_setdefault_del -
1290 : *
1291 : * Set foreign key references to defaults at delete event on PK table.
1292 : */
1293 : Datum
1294 56 : RI_FKey_setdefault_del(PG_FUNCTION_ARGS)
1295 : {
1296 : /* Check that this is a valid trigger call on the right time and event. */
1297 56 : ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_del", RI_TRIGTYPE_DELETE);
1298 :
1299 : /* Share code with UPDATE case */
1300 56 : return ri_set((TriggerData *) fcinfo->context, false, RI_TRIGTYPE_DELETE);
1301 : }
1302 :
1303 : /*
1304 : * RI_FKey_setdefault_upd -
1305 : *
1306 : * Set foreign key references to defaults at update event on PK table.
1307 : */
1308 : Datum
1309 32 : RI_FKey_setdefault_upd(PG_FUNCTION_ARGS)
1310 : {
1311 : /* Check that this is a valid trigger call on the right time and event. */
1312 32 : ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_upd", RI_TRIGTYPE_UPDATE);
1313 :
1314 : /* Share code with DELETE case */
1315 32 : return ri_set((TriggerData *) fcinfo->context, false, RI_TRIGTYPE_UPDATE);
1316 : }
1317 :
1318 : /*
1319 : * ri_set -
1320 : *
1321 : * Common code for ON DELETE SET NULL, ON DELETE SET DEFAULT, ON UPDATE SET
1322 : * NULL, and ON UPDATE SET DEFAULT.
1323 : */
1324 : static Datum
1325 173 : ri_set(TriggerData *trigdata, bool is_set_null, int tgkind)
1326 : {
1327 : const RI_ConstraintInfo *riinfo;
1328 : Relation fk_rel;
1329 : Relation pk_rel;
1330 : TupleTableSlot *oldslot;
1331 : RI_QueryKey qkey;
1332 : SPIPlanPtr qplan;
1333 : int32 queryno;
1334 :
1335 173 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
1336 : trigdata->tg_relation, true);
1337 :
1338 : /*
1339 : * Get the relation descriptors of the FK and PK tables and the old tuple.
1340 : *
1341 : * fk_rel is opened in RowExclusiveLock mode since that's what our
1342 : * eventual UPDATE will get on it.
1343 : */
1344 173 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
1345 173 : pk_rel = trigdata->tg_relation;
1346 173 : oldslot = trigdata->tg_trigslot;
1347 :
1348 173 : SPI_connect();
1349 :
1350 : /*
1351 : * Fetch or prepare a saved plan for the trigger.
1352 : */
1353 173 : switch (tgkind)
1354 : {
1355 52 : case RI_TRIGTYPE_UPDATE:
1356 52 : queryno = is_set_null
1357 : ? RI_PLAN_SETNULL_ONUPDATE
1358 52 : : RI_PLAN_SETDEFAULT_ONUPDATE;
1359 52 : break;
1360 121 : case RI_TRIGTYPE_DELETE:
1361 121 : queryno = is_set_null
1362 : ? RI_PLAN_SETNULL_ONDELETE
1363 121 : : RI_PLAN_SETDEFAULT_ONDELETE;
1364 121 : break;
1365 0 : default:
1366 0 : elog(ERROR, "invalid tgkind passed to ri_set");
1367 : }
1368 :
1369 173 : ri_BuildQueryKey(&qkey, riinfo, queryno);
1370 :
1371 173 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
1372 : {
1373 : StringInfoData querybuf;
1374 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1375 : char attname[MAX_QUOTED_NAME_LEN];
1376 : char paramname[16];
1377 : const char *querysep;
1378 : const char *qualsep;
1379 : Oid queryoids[RI_MAX_NUMKEYS];
1380 : const char *fk_only;
1381 : int num_cols_to_set;
1382 : const int16 *set_cols;
1383 :
1384 103 : switch (tgkind)
1385 : {
1386 32 : case RI_TRIGTYPE_UPDATE:
1387 32 : num_cols_to_set = riinfo->nkeys;
1388 32 : set_cols = riinfo->fk_attnums;
1389 32 : break;
1390 71 : case RI_TRIGTYPE_DELETE:
1391 :
1392 : /*
1393 : * If confdelsetcols are present, then we only update the
1394 : * columns specified in that array, otherwise we update all
1395 : * the referencing columns.
1396 : */
1397 71 : if (riinfo->ndelsetcols != 0)
1398 : {
1399 16 : num_cols_to_set = riinfo->ndelsetcols;
1400 16 : set_cols = riinfo->confdelsetcols;
1401 : }
1402 : else
1403 : {
1404 55 : num_cols_to_set = riinfo->nkeys;
1405 55 : set_cols = riinfo->fk_attnums;
1406 : }
1407 71 : break;
1408 0 : default:
1409 0 : elog(ERROR, "invalid tgkind passed to ri_set");
1410 : }
1411 :
1412 : /* ----------
1413 : * The query string built is
1414 : * UPDATE [ONLY] <fktable> SET fkatt1 = {NULL|DEFAULT} [, ...]
1415 : * WHERE $1 = fkatt1 [AND ...]
1416 : * The type id's for the $ parameters are those of the
1417 : * corresponding PK attributes.
1418 : * ----------
1419 : */
1420 103 : initStringInfo(&querybuf);
1421 206 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1422 103 : "" : "ONLY ";
1423 103 : quoteRelationName(fkrelname, fk_rel);
1424 103 : appendStringInfo(&querybuf, "UPDATE %s%s SET",
1425 : fk_only, fkrelname);
1426 :
1427 : /*
1428 : * Add assignment clauses
1429 : */
1430 103 : querysep = "";
1431 272 : for (int i = 0; i < num_cols_to_set; i++)
1432 : {
1433 169 : quoteOneName(attname, RIAttName(fk_rel, set_cols[i]));
1434 169 : appendStringInfo(&querybuf,
1435 : "%s %s = %s",
1436 : querysep, attname,
1437 : is_set_null ? "NULL" : "DEFAULT");
1438 169 : querysep = ",";
1439 : }
1440 :
1441 : /*
1442 : * Add WHERE clause
1443 : */
1444 103 : qualsep = "WHERE";
1445 288 : for (int i = 0; i < riinfo->nkeys; i++)
1446 : {
1447 185 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1448 185 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1449 :
1450 185 : quoteOneName(attname,
1451 185 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1452 :
1453 185 : sprintf(paramname, "$%d", i + 1);
1454 185 : ri_GenerateQual(&querybuf, qualsep,
1455 : paramname, pk_type,
1456 185 : riinfo->pf_eq_oprs[i],
1457 : attname, fk_type);
1458 185 : qualsep = "AND";
1459 185 : queryoids[i] = pk_type;
1460 : }
1461 :
1462 : /* Prepare and save the plan */
1463 103 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
1464 : &qkey, fk_rel, pk_rel);
1465 : }
1466 :
1467 : /*
1468 : * We have a plan now. Run it to update the existing references.
1469 : */
1470 173 : ri_PerformCheck(riinfo, &qkey, qplan,
1471 : fk_rel, pk_rel,
1472 : oldslot, NULL,
1473 : false,
1474 : true, /* must detect new rows */
1475 : SPI_OK_UPDATE);
1476 :
1477 172 : if (SPI_finish() != SPI_OK_FINISH)
1478 0 : elog(ERROR, "SPI_finish failed");
1479 :
1480 172 : table_close(fk_rel, RowExclusiveLock);
1481 :
1482 172 : if (is_set_null)
1483 84 : return PointerGetDatum(NULL);
1484 : else
1485 : {
1486 : /*
1487 : * If we just deleted or updated the PK row whose key was equal to the
1488 : * FK columns' default values, and a referencing row exists in the FK
1489 : * table, we would have updated that row to the same values it already
1490 : * had --- and RI_FKey_fk_upd_check_required would hence believe no
1491 : * check is necessary. So we need to do another lookup now and in
1492 : * case a reference still exists, abort the operation. That is
1493 : * already implemented in the NO ACTION trigger, so just run it. (This
1494 : * recheck is only needed in the SET DEFAULT case, since CASCADE would
1495 : * remove such rows in case of a DELETE operation or would change the
1496 : * FK key values in case of an UPDATE, while SET NULL is certain to
1497 : * result in rows that satisfy the FK constraint.)
1498 : */
1499 88 : return ri_restrict(trigdata, true);
1500 : }
1501 : }
1502 :
1503 :
1504 : /*
1505 : * RI_FKey_pk_upd_check_required -
1506 : *
1507 : * Check if we really need to fire the RI trigger for an update or delete to a PK
1508 : * relation. This is called by the AFTER trigger queue manager to see if
1509 : * it can skip queuing an instance of an RI trigger. Returns true if the
1510 : * trigger must be fired, false if we can prove the constraint will still
1511 : * be satisfied.
1512 : *
1513 : * newslot will be NULL if this is called for a delete.
1514 : */
1515 : bool
1516 1532 : RI_FKey_pk_upd_check_required(Trigger *trigger, Relation pk_rel,
1517 : TupleTableSlot *oldslot, TupleTableSlot *newslot)
1518 : {
1519 : const RI_ConstraintInfo *riinfo;
1520 :
1521 1532 : riinfo = ri_FetchConstraintInfo(trigger, pk_rel, true);
1522 :
1523 : /*
1524 : * If any old key value is NULL, the row could not have been referenced by
1525 : * an FK row, so no check is needed.
1526 : */
1527 1532 : if (ri_NullCheck(RelationGetDescr(pk_rel), oldslot, riinfo, true) != RI_KEYS_NONE_NULL)
1528 4 : return false;
1529 :
1530 : /* If all old and new key values are equal, no check is needed */
1531 1528 : if (newslot && ri_KeysEqual(pk_rel, oldslot, newslot, riinfo, true))
1532 288 : return false;
1533 :
1534 : /* Else we need to fire the trigger. */
1535 1240 : return true;
1536 : }
1537 :
1538 : /*
1539 : * RI_FKey_fk_upd_check_required -
1540 : *
1541 : * Check if we really need to fire the RI trigger for an update to an FK
1542 : * relation. This is called by the AFTER trigger queue manager to see if
1543 : * it can skip queuing an instance of an RI trigger. Returns true if the
1544 : * trigger must be fired, false if we can prove the constraint will still
1545 : * be satisfied.
1546 : */
1547 : bool
1548 668 : RI_FKey_fk_upd_check_required(Trigger *trigger, Relation fk_rel,
1549 : TupleTableSlot *oldslot, TupleTableSlot *newslot)
1550 : {
1551 : const RI_ConstraintInfo *riinfo;
1552 : int ri_nullcheck;
1553 :
1554 : /*
1555 : * AfterTriggerSaveEvent() handles things such that this function is never
1556 : * called for partitioned tables.
1557 : */
1558 : Assert(fk_rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE);
1559 :
1560 668 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1561 :
1562 668 : ri_nullcheck = ri_NullCheck(RelationGetDescr(fk_rel), newslot, riinfo, false);
1563 :
1564 : /*
1565 : * If all new key values are NULL, the row satisfies the constraint, so no
1566 : * check is needed.
1567 : */
1568 668 : if (ri_nullcheck == RI_KEYS_ALL_NULL)
1569 84 : return false;
1570 :
1571 : /*
1572 : * If some new key values are NULL, the behavior depends on the match
1573 : * type.
1574 : */
1575 584 : else if (ri_nullcheck == RI_KEYS_SOME_NULL)
1576 : {
1577 20 : switch (riinfo->confmatchtype)
1578 : {
1579 16 : case FKCONSTR_MATCH_SIMPLE:
1580 :
1581 : /*
1582 : * If any new key value is NULL, the row must satisfy the
1583 : * constraint, so no check is needed.
1584 : */
1585 16 : return false;
1586 :
1587 0 : case FKCONSTR_MATCH_PARTIAL:
1588 :
1589 : /*
1590 : * Don't know, must run full check.
1591 : */
1592 0 : break;
1593 :
1594 4 : case FKCONSTR_MATCH_FULL:
1595 :
1596 : /*
1597 : * If some new key values are NULL, the row fails the
1598 : * constraint. We must not throw error here, because the row
1599 : * might get invalidated before the constraint is to be
1600 : * checked, but we should queue the event to apply the check
1601 : * later.
1602 : */
1603 4 : return true;
1604 : }
1605 : }
1606 :
1607 : /*
1608 : * Continues here for no new key values are NULL, or we couldn't decide
1609 : * yet.
1610 : */
1611 :
1612 : /*
1613 : * If the original row was inserted by our own transaction, we must fire
1614 : * the trigger whether or not the keys are equal. This is because our
1615 : * UPDATE will invalidate the INSERT so that the INSERT RI trigger will
1616 : * not do anything; so we had better do the UPDATE check. (We could skip
1617 : * this if we knew the INSERT trigger already fired, but there is no easy
1618 : * way to know that.)
1619 : */
1620 564 : if (slot_is_current_xact_tuple(oldslot))
1621 77 : return true;
1622 :
1623 : /* If all old and new key values are equal, no check is needed */
1624 487 : if (ri_KeysEqual(fk_rel, oldslot, newslot, riinfo, false))
1625 262 : return false;
1626 :
1627 : /* Else we need to fire the trigger. */
1628 225 : return true;
1629 : }
1630 :
1631 : /*
1632 : * RI_Initial_Check -
1633 : *
1634 : * Check an entire table for non-matching values using a single query.
1635 : * This is not a trigger procedure, but is called during ALTER TABLE
1636 : * ADD FOREIGN KEY to validate the initial table contents.
1637 : *
1638 : * We expect that the caller has made provision to prevent any problems
1639 : * caused by concurrent actions. This could be either by locking rel and
1640 : * pkrel at ShareRowExclusiveLock or higher, or by otherwise ensuring
1641 : * that triggers implementing the checks are already active.
1642 : * Hence, we do not need to lock individual rows for the check.
1643 : *
1644 : * If the check fails because the current user doesn't have permissions
1645 : * to read both tables, return false to let our caller know that they will
1646 : * need to do something else to check the constraint.
1647 : */
1648 : bool
1649 765 : RI_Initial_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
1650 : {
1651 : const RI_ConstraintInfo *riinfo;
1652 : StringInfoData querybuf;
1653 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
1654 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1655 : char pkattname[MAX_QUOTED_NAME_LEN + 3];
1656 : char fkattname[MAX_QUOTED_NAME_LEN + 3];
1657 : RangeTblEntry *rte;
1658 : RTEPermissionInfo *pk_perminfo;
1659 : RTEPermissionInfo *fk_perminfo;
1660 765 : List *rtes = NIL;
1661 765 : List *perminfos = NIL;
1662 : const char *sep;
1663 : const char *fk_only;
1664 : const char *pk_only;
1665 : int save_nestlevel;
1666 : char workmembuf[32];
1667 : int spi_result;
1668 : SPIPlanPtr qplan;
1669 :
1670 765 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1671 :
1672 : /*
1673 : * Check to make sure current user has enough permissions to do the test
1674 : * query. (If not, caller can fall back to the trigger method, which
1675 : * works because it changes user IDs on the fly.)
1676 : *
1677 : * XXX are there any other show-stopper conditions to check?
1678 : */
1679 765 : pk_perminfo = makeNode(RTEPermissionInfo);
1680 765 : pk_perminfo->relid = RelationGetRelid(pk_rel);
1681 765 : pk_perminfo->requiredPerms = ACL_SELECT;
1682 765 : perminfos = lappend(perminfos, pk_perminfo);
1683 765 : rte = makeNode(RangeTblEntry);
1684 765 : rte->rtekind = RTE_RELATION;
1685 765 : rte->relid = RelationGetRelid(pk_rel);
1686 765 : rte->relkind = pk_rel->rd_rel->relkind;
1687 765 : rte->rellockmode = AccessShareLock;
1688 765 : rte->perminfoindex = list_length(perminfos);
1689 765 : rtes = lappend(rtes, rte);
1690 :
1691 765 : fk_perminfo = makeNode(RTEPermissionInfo);
1692 765 : fk_perminfo->relid = RelationGetRelid(fk_rel);
1693 765 : fk_perminfo->requiredPerms = ACL_SELECT;
1694 765 : perminfos = lappend(perminfos, fk_perminfo);
1695 765 : rte = makeNode(RangeTblEntry);
1696 765 : rte->rtekind = RTE_RELATION;
1697 765 : rte->relid = RelationGetRelid(fk_rel);
1698 765 : rte->relkind = fk_rel->rd_rel->relkind;
1699 765 : rte->rellockmode = AccessShareLock;
1700 765 : rte->perminfoindex = list_length(perminfos);
1701 765 : rtes = lappend(rtes, rte);
1702 :
1703 1799 : for (int i = 0; i < riinfo->nkeys; i++)
1704 : {
1705 : int attno;
1706 :
1707 1034 : attno = riinfo->pk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
1708 1034 : pk_perminfo->selectedCols = bms_add_member(pk_perminfo->selectedCols, attno);
1709 :
1710 1034 : attno = riinfo->fk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
1711 1034 : fk_perminfo->selectedCols = bms_add_member(fk_perminfo->selectedCols, attno);
1712 : }
1713 :
1714 765 : if (!ExecCheckPermissions(rtes, perminfos, false))
1715 8 : return false;
1716 :
1717 : /*
1718 : * Also punt if RLS is enabled on either table unless this role has the
1719 : * bypassrls right or is the table owner of the table(s) involved which
1720 : * have RLS enabled.
1721 : */
1722 757 : if (!has_bypassrls_privilege(GetUserId()) &&
1723 0 : ((pk_rel->rd_rel->relrowsecurity &&
1724 0 : !object_ownercheck(RelationRelationId, RelationGetRelid(pk_rel),
1725 0 : GetUserId())) ||
1726 0 : (fk_rel->rd_rel->relrowsecurity &&
1727 0 : !object_ownercheck(RelationRelationId, RelationGetRelid(fk_rel),
1728 : GetUserId()))))
1729 0 : return false;
1730 :
1731 : /*----------
1732 : * The query string built is:
1733 : * SELECT fk.keycols FROM [ONLY] relname fk
1734 : * LEFT OUTER JOIN [ONLY] pkrelname pk
1735 : * ON (pk.pkkeycol1=fk.keycol1 [AND ...])
1736 : * WHERE pk.pkkeycol1 IS NULL AND
1737 : * For MATCH SIMPLE:
1738 : * (fk.keycol1 IS NOT NULL [AND ...])
1739 : * For MATCH FULL:
1740 : * (fk.keycol1 IS NOT NULL [OR ...])
1741 : *
1742 : * We attach COLLATE clauses to the operators when comparing columns
1743 : * that have different collations.
1744 : *----------
1745 : */
1746 757 : initStringInfo(&querybuf);
1747 757 : appendStringInfoString(&querybuf, "SELECT ");
1748 757 : sep = "";
1749 1775 : for (int i = 0; i < riinfo->nkeys; i++)
1750 : {
1751 1018 : quoteOneName(fkattname,
1752 1018 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1753 1018 : appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
1754 1018 : sep = ", ";
1755 : }
1756 :
1757 757 : quoteRelationName(pkrelname, pk_rel);
1758 757 : quoteRelationName(fkrelname, fk_rel);
1759 1514 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1760 757 : "" : "ONLY ";
1761 1514 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1762 757 : "" : "ONLY ";
1763 757 : appendStringInfo(&querybuf,
1764 : " FROM %s%s fk LEFT OUTER JOIN %s%s pk ON",
1765 : fk_only, fkrelname, pk_only, pkrelname);
1766 :
1767 757 : strcpy(pkattname, "pk.");
1768 757 : strcpy(fkattname, "fk.");
1769 757 : sep = "(";
1770 1775 : for (int i = 0; i < riinfo->nkeys; i++)
1771 : {
1772 1018 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1773 1018 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1774 1018 : Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
1775 1018 : Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
1776 :
1777 1018 : quoteOneName(pkattname + 3,
1778 1018 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
1779 1018 : quoteOneName(fkattname + 3,
1780 1018 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1781 1018 : ri_GenerateQual(&querybuf, sep,
1782 : pkattname, pk_type,
1783 1018 : riinfo->pf_eq_oprs[i],
1784 : fkattname, fk_type);
1785 1018 : if (pk_coll != fk_coll)
1786 8 : ri_GenerateQualCollation(&querybuf, pk_coll);
1787 1018 : sep = "AND";
1788 : }
1789 :
1790 : /*
1791 : * It's sufficient to test any one pk attribute for null to detect a join
1792 : * failure.
1793 : */
1794 757 : quoteOneName(pkattname, RIAttName(pk_rel, riinfo->pk_attnums[0]));
1795 757 : appendStringInfo(&querybuf, ") WHERE pk.%s IS NULL AND (", pkattname);
1796 :
1797 757 : sep = "";
1798 1775 : for (int i = 0; i < riinfo->nkeys; i++)
1799 : {
1800 1018 : quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
1801 1018 : appendStringInfo(&querybuf,
1802 : "%sfk.%s IS NOT NULL",
1803 : sep, fkattname);
1804 1018 : switch (riinfo->confmatchtype)
1805 : {
1806 944 : case FKCONSTR_MATCH_SIMPLE:
1807 944 : sep = " AND ";
1808 944 : break;
1809 74 : case FKCONSTR_MATCH_FULL:
1810 74 : sep = " OR ";
1811 74 : break;
1812 : }
1813 : }
1814 757 : appendStringInfoChar(&querybuf, ')');
1815 :
1816 : /*
1817 : * Temporarily increase work_mem so that the check query can be executed
1818 : * more efficiently. It seems okay to do this because the query is simple
1819 : * enough to not use a multiple of work_mem, and one typically would not
1820 : * have many large foreign-key validations happening concurrently. So
1821 : * this seems to meet the criteria for being considered a "maintenance"
1822 : * operation, and accordingly we use maintenance_work_mem. However, we
1823 : * must also set hash_mem_multiplier to 1, since it is surely not okay to
1824 : * let that get applied to the maintenance_work_mem value.
1825 : *
1826 : * We use the equivalent of a function SET option to allow the setting to
1827 : * persist for exactly the duration of the check query. guc.c also takes
1828 : * care of undoing the setting on error.
1829 : */
1830 757 : save_nestlevel = NewGUCNestLevel();
1831 :
1832 757 : snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
1833 757 : (void) set_config_option("work_mem", workmembuf,
1834 : PGC_USERSET, PGC_S_SESSION,
1835 : GUC_ACTION_SAVE, true, 0, false);
1836 757 : (void) set_config_option("hash_mem_multiplier", "1",
1837 : PGC_USERSET, PGC_S_SESSION,
1838 : GUC_ACTION_SAVE, true, 0, false);
1839 :
1840 757 : SPI_connect();
1841 :
1842 : /*
1843 : * Generate the plan. We don't need to cache it, and there are no
1844 : * arguments to the plan.
1845 : */
1846 757 : qplan = SPI_prepare(querybuf.data, 0, NULL);
1847 :
1848 757 : if (qplan == NULL)
1849 0 : elog(ERROR, "SPI_prepare returned %s for %s",
1850 : SPI_result_code_string(SPI_result), querybuf.data);
1851 :
1852 : /*
1853 : * Run the plan. For safety we force a current snapshot to be used. (In
1854 : * transaction-snapshot mode, this arguably violates transaction isolation
1855 : * rules, but we really haven't got much choice.) We don't need to
1856 : * register the snapshot, because SPI_execute_snapshot will see to it. We
1857 : * need at most one tuple returned, so pass limit = 1.
1858 : */
1859 757 : spi_result = SPI_execute_snapshot(qplan,
1860 : NULL, NULL,
1861 : GetLatestSnapshot(),
1862 : InvalidSnapshot,
1863 : true, false, 1);
1864 :
1865 : /* Check result */
1866 757 : if (spi_result != SPI_OK_SELECT)
1867 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
1868 :
1869 : /* Did we find a tuple violating the constraint? */
1870 757 : if (SPI_processed > 0)
1871 : {
1872 : TupleTableSlot *slot;
1873 59 : HeapTuple tuple = SPI_tuptable->vals[0];
1874 59 : TupleDesc tupdesc = SPI_tuptable->tupdesc;
1875 : RI_ConstraintInfo fake_riinfo;
1876 :
1877 59 : slot = MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual);
1878 :
1879 59 : heap_deform_tuple(tuple, tupdesc,
1880 : slot->tts_values, slot->tts_isnull);
1881 59 : ExecStoreVirtualTuple(slot);
1882 :
1883 : /*
1884 : * The columns to look at in the result tuple are 1..N, not whatever
1885 : * they are in the fk_rel. Hack up riinfo so that the subroutines
1886 : * called here will behave properly.
1887 : *
1888 : * In addition to this, we have to pass the correct tupdesc to
1889 : * ri_ReportViolation, overriding its normal habit of using the pk_rel
1890 : * or fk_rel's tupdesc.
1891 : */
1892 59 : memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
1893 134 : for (int i = 0; i < fake_riinfo.nkeys; i++)
1894 75 : fake_riinfo.fk_attnums[i] = i + 1;
1895 :
1896 : /*
1897 : * If it's MATCH FULL, and there are any nulls in the FK keys,
1898 : * complain about that rather than the lack of a match. MATCH FULL
1899 : * disallows partially-null FK rows.
1900 : */
1901 79 : if (fake_riinfo.confmatchtype == FKCONSTR_MATCH_FULL &&
1902 20 : ri_NullCheck(tupdesc, slot, &fake_riinfo, false) != RI_KEYS_NONE_NULL)
1903 8 : ereport(ERROR,
1904 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
1905 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
1906 : RelationGetRelationName(fk_rel),
1907 : NameStr(fake_riinfo.conname)),
1908 : errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
1909 : errtableconstraint(fk_rel,
1910 : NameStr(fake_riinfo.conname))));
1911 :
1912 : /*
1913 : * We tell ri_ReportViolation we were doing the RI_PLAN_CHECK_LOOKUPPK
1914 : * query, which isn't true, but will cause it to use
1915 : * fake_riinfo.fk_attnums as we need.
1916 : */
1917 51 : ri_ReportViolation(&fake_riinfo,
1918 : pk_rel, fk_rel,
1919 : slot, tupdesc,
1920 : RI_PLAN_CHECK_LOOKUPPK, false, false);
1921 :
1922 : ExecDropSingleTupleTableSlot(slot);
1923 : }
1924 :
1925 698 : if (SPI_finish() != SPI_OK_FINISH)
1926 0 : elog(ERROR, "SPI_finish failed");
1927 :
1928 : /*
1929 : * Restore work_mem and hash_mem_multiplier.
1930 : */
1931 698 : AtEOXact_GUC(true, save_nestlevel);
1932 :
1933 698 : return true;
1934 : }
1935 :
1936 : /*
1937 : * RI_PartitionRemove_Check -
1938 : *
1939 : * Verify no referencing values exist, when a partition is detached on
1940 : * the referenced side of a foreign key constraint.
1941 : */
1942 : void
1943 65 : RI_PartitionRemove_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
1944 : {
1945 : const RI_ConstraintInfo *riinfo;
1946 : StringInfoData querybuf;
1947 : char *constraintDef;
1948 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
1949 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1950 : char pkattname[MAX_QUOTED_NAME_LEN + 3];
1951 : char fkattname[MAX_QUOTED_NAME_LEN + 3];
1952 : const char *sep;
1953 : const char *fk_only;
1954 : int save_nestlevel;
1955 : char workmembuf[32];
1956 : int spi_result;
1957 : SPIPlanPtr qplan;
1958 : int i;
1959 :
1960 65 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1961 :
1962 : /*
1963 : * We don't check permissions before displaying the error message, on the
1964 : * assumption that the user detaching the partition must have enough
1965 : * privileges to examine the table contents anyhow.
1966 : */
1967 :
1968 : /*----------
1969 : * The query string built is:
1970 : * SELECT fk.keycols FROM [ONLY] relname fk
1971 : * JOIN pkrelname pk
1972 : * ON (pk.pkkeycol1=fk.keycol1 [AND ...])
1973 : * WHERE (<partition constraint>) AND
1974 : * For MATCH SIMPLE:
1975 : * (fk.keycol1 IS NOT NULL [AND ...])
1976 : * For MATCH FULL:
1977 : * (fk.keycol1 IS NOT NULL [OR ...])
1978 : *
1979 : * We attach COLLATE clauses to the operators when comparing columns
1980 : * that have different collations.
1981 : *----------
1982 : */
1983 65 : initStringInfo(&querybuf);
1984 65 : appendStringInfoString(&querybuf, "SELECT ");
1985 65 : sep = "";
1986 130 : for (i = 0; i < riinfo->nkeys; i++)
1987 : {
1988 65 : quoteOneName(fkattname,
1989 65 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1990 65 : appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
1991 65 : sep = ", ";
1992 : }
1993 :
1994 65 : quoteRelationName(pkrelname, pk_rel);
1995 65 : quoteRelationName(fkrelname, fk_rel);
1996 130 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1997 65 : "" : "ONLY ";
1998 65 : appendStringInfo(&querybuf,
1999 : " FROM %s%s fk JOIN %s pk ON",
2000 : fk_only, fkrelname, pkrelname);
2001 65 : strcpy(pkattname, "pk.");
2002 65 : strcpy(fkattname, "fk.");
2003 65 : sep = "(";
2004 130 : for (i = 0; i < riinfo->nkeys; i++)
2005 : {
2006 65 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
2007 65 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
2008 65 : Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
2009 65 : Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
2010 :
2011 65 : quoteOneName(pkattname + 3,
2012 65 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
2013 65 : quoteOneName(fkattname + 3,
2014 65 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
2015 65 : ri_GenerateQual(&querybuf, sep,
2016 : pkattname, pk_type,
2017 65 : riinfo->pf_eq_oprs[i],
2018 : fkattname, fk_type);
2019 65 : if (pk_coll != fk_coll)
2020 0 : ri_GenerateQualCollation(&querybuf, pk_coll);
2021 65 : sep = "AND";
2022 : }
2023 :
2024 : /*
2025 : * Start the WHERE clause with the partition constraint (except if this is
2026 : * the default partition and there's no other partition, because the
2027 : * partition constraint is the empty string in that case.)
2028 : */
2029 65 : constraintDef = pg_get_partconstrdef_string(RelationGetRelid(pk_rel), "pk");
2030 65 : if (constraintDef && constraintDef[0] != '\0')
2031 65 : appendStringInfo(&querybuf, ") WHERE %s AND (",
2032 : constraintDef);
2033 : else
2034 0 : appendStringInfoString(&querybuf, ") WHERE (");
2035 :
2036 65 : sep = "";
2037 130 : for (i = 0; i < riinfo->nkeys; i++)
2038 : {
2039 65 : quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
2040 65 : appendStringInfo(&querybuf,
2041 : "%sfk.%s IS NOT NULL",
2042 : sep, fkattname);
2043 65 : switch (riinfo->confmatchtype)
2044 : {
2045 65 : case FKCONSTR_MATCH_SIMPLE:
2046 65 : sep = " AND ";
2047 65 : break;
2048 0 : case FKCONSTR_MATCH_FULL:
2049 0 : sep = " OR ";
2050 0 : break;
2051 : }
2052 : }
2053 65 : appendStringInfoChar(&querybuf, ')');
2054 :
2055 : /*
2056 : * Temporarily increase work_mem so that the check query can be executed
2057 : * more efficiently. It seems okay to do this because the query is simple
2058 : * enough to not use a multiple of work_mem, and one typically would not
2059 : * have many large foreign-key validations happening concurrently. So
2060 : * this seems to meet the criteria for being considered a "maintenance"
2061 : * operation, and accordingly we use maintenance_work_mem. However, we
2062 : * must also set hash_mem_multiplier to 1, since it is surely not okay to
2063 : * let that get applied to the maintenance_work_mem value.
2064 : *
2065 : * We use the equivalent of a function SET option to allow the setting to
2066 : * persist for exactly the duration of the check query. guc.c also takes
2067 : * care of undoing the setting on error.
2068 : */
2069 65 : save_nestlevel = NewGUCNestLevel();
2070 :
2071 65 : snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
2072 65 : (void) set_config_option("work_mem", workmembuf,
2073 : PGC_USERSET, PGC_S_SESSION,
2074 : GUC_ACTION_SAVE, true, 0, false);
2075 65 : (void) set_config_option("hash_mem_multiplier", "1",
2076 : PGC_USERSET, PGC_S_SESSION,
2077 : GUC_ACTION_SAVE, true, 0, false);
2078 :
2079 65 : SPI_connect();
2080 :
2081 : /*
2082 : * Generate the plan. We don't need to cache it, and there are no
2083 : * arguments to the plan.
2084 : */
2085 65 : qplan = SPI_prepare(querybuf.data, 0, NULL);
2086 :
2087 65 : if (qplan == NULL)
2088 0 : elog(ERROR, "SPI_prepare returned %s for %s",
2089 : SPI_result_code_string(SPI_result), querybuf.data);
2090 :
2091 : /*
2092 : * Run the plan. For safety we force a current snapshot to be used. (In
2093 : * transaction-snapshot mode, this arguably violates transaction isolation
2094 : * rules, but we really haven't got much choice.) We don't need to
2095 : * register the snapshot, because SPI_execute_snapshot will see to it. We
2096 : * need at most one tuple returned, so pass limit = 1.
2097 : */
2098 65 : spi_result = SPI_execute_snapshot(qplan,
2099 : NULL, NULL,
2100 : GetLatestSnapshot(),
2101 : InvalidSnapshot,
2102 : true, false, 1);
2103 :
2104 : /* Check result */
2105 65 : if (spi_result != SPI_OK_SELECT)
2106 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
2107 :
2108 : /* Did we find a tuple that would violate the constraint? */
2109 65 : if (SPI_processed > 0)
2110 : {
2111 : TupleTableSlot *slot;
2112 22 : HeapTuple tuple = SPI_tuptable->vals[0];
2113 22 : TupleDesc tupdesc = SPI_tuptable->tupdesc;
2114 : RI_ConstraintInfo fake_riinfo;
2115 :
2116 22 : slot = MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual);
2117 :
2118 22 : heap_deform_tuple(tuple, tupdesc,
2119 : slot->tts_values, slot->tts_isnull);
2120 22 : ExecStoreVirtualTuple(slot);
2121 :
2122 : /*
2123 : * The columns to look at in the result tuple are 1..N, not whatever
2124 : * they are in the fk_rel. Hack up riinfo so that ri_ReportViolation
2125 : * will behave properly.
2126 : *
2127 : * In addition to this, we have to pass the correct tupdesc to
2128 : * ri_ReportViolation, overriding its normal habit of using the pk_rel
2129 : * or fk_rel's tupdesc.
2130 : */
2131 22 : memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
2132 44 : for (i = 0; i < fake_riinfo.nkeys; i++)
2133 22 : fake_riinfo.pk_attnums[i] = i + 1;
2134 :
2135 22 : ri_ReportViolation(&fake_riinfo, pk_rel, fk_rel,
2136 : slot, tupdesc, 0, false, true);
2137 : }
2138 :
2139 43 : if (SPI_finish() != SPI_OK_FINISH)
2140 0 : elog(ERROR, "SPI_finish failed");
2141 :
2142 : /*
2143 : * Restore work_mem and hash_mem_multiplier.
2144 : */
2145 43 : AtEOXact_GUC(true, save_nestlevel);
2146 43 : }
2147 :
2148 :
2149 : /* ----------
2150 : * Local functions below
2151 : * ----------
2152 : */
2153 :
2154 :
2155 : /*
2156 : * quoteOneName --- safely quote a single SQL name
2157 : *
2158 : * buffer must be MAX_QUOTED_NAME_LEN long (includes room for \0)
2159 : */
2160 : static void
2161 13098 : quoteOneName(char *buffer, const char *name)
2162 : {
2163 : /* Rather than trying to be smart, just always quote it. */
2164 13098 : *buffer++ = '"';
2165 80816 : while (*name)
2166 : {
2167 67718 : if (*name == '"')
2168 0 : *buffer++ = '"';
2169 67718 : *buffer++ = *name++;
2170 : }
2171 13098 : *buffer++ = '"';
2172 13098 : *buffer = '\0';
2173 13098 : }
2174 :
2175 : /*
2176 : * quoteRelationName --- safely quote a fully qualified relation name
2177 : *
2178 : * buffer must be MAX_QUOTED_REL_NAME_LEN long (includes room for \0)
2179 : */
2180 : static void
2181 2900 : quoteRelationName(char *buffer, Relation rel)
2182 : {
2183 2900 : quoteOneName(buffer, get_namespace_name(RelationGetNamespace(rel)));
2184 2900 : buffer += strlen(buffer);
2185 2900 : *buffer++ = '.';
2186 2900 : quoteOneName(buffer, RelationGetRelationName(rel));
2187 2900 : }
2188 :
2189 : /*
2190 : * ri_GenerateQual --- generate a WHERE clause equating two variables
2191 : *
2192 : * This basically appends " sep leftop op rightop" to buf, adding casts
2193 : * and schema qualification as needed to ensure that the parser will select
2194 : * the operator we specify. leftop and rightop should be parenthesized
2195 : * if they aren't variables or parameters.
2196 : */
2197 : static void
2198 3107 : ri_GenerateQual(StringInfo buf,
2199 : const char *sep,
2200 : const char *leftop, Oid leftoptype,
2201 : Oid opoid,
2202 : const char *rightop, Oid rightoptype)
2203 : {
2204 3107 : appendStringInfo(buf, " %s ", sep);
2205 3107 : generate_operator_clause(buf, leftop, leftoptype, opoid,
2206 : rightop, rightoptype);
2207 3107 : }
2208 :
2209 : /*
2210 : * ri_GenerateQualCollation --- add a COLLATE spec to a WHERE clause
2211 : *
2212 : * We only have to use this function when directly comparing the referencing
2213 : * and referenced columns, if they are of different collations; else the
2214 : * parser will fail to resolve the collation to use. We don't need to use
2215 : * this function for RI queries that compare a variable to a $n parameter.
2216 : * Since parameter symbols always have default collation, the effect will be
2217 : * to use the variable's collation.
2218 : *
2219 : * Note that we require that the collations of the referencing and the
2220 : * referenced column have the same notion of equality: Either they have to
2221 : * both be deterministic or else they both have to be the same. (See also
2222 : * ATAddForeignKeyConstraint().)
2223 : */
2224 : static void
2225 8 : ri_GenerateQualCollation(StringInfo buf, Oid collation)
2226 : {
2227 : HeapTuple tp;
2228 : Form_pg_collation colltup;
2229 : char *collname;
2230 : char onename[MAX_QUOTED_NAME_LEN];
2231 :
2232 : /* Nothing to do if it's a noncollatable data type */
2233 8 : if (!OidIsValid(collation))
2234 0 : return;
2235 :
2236 8 : tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(collation));
2237 8 : if (!HeapTupleIsValid(tp))
2238 0 : elog(ERROR, "cache lookup failed for collation %u", collation);
2239 8 : colltup = (Form_pg_collation) GETSTRUCT(tp);
2240 8 : collname = NameStr(colltup->collname);
2241 :
2242 : /*
2243 : * We qualify the name always, for simplicity and to ensure the query is
2244 : * not search-path-dependent.
2245 : */
2246 8 : quoteOneName(onename, get_namespace_name(colltup->collnamespace));
2247 8 : appendStringInfo(buf, " COLLATE %s", onename);
2248 8 : quoteOneName(onename, collname);
2249 8 : appendStringInfo(buf, ".%s", onename);
2250 :
2251 8 : ReleaseSysCache(tp);
2252 : }
2253 :
2254 : /* ----------
2255 : * ri_BuildQueryKey -
2256 : *
2257 : * Construct a hashtable key for a prepared SPI plan of an FK constraint.
2258 : *
2259 : * key: output argument, *key is filled in based on the other arguments
2260 : * riinfo: info derived from pg_constraint entry
2261 : * constr_queryno: an internal number identifying the query type
2262 : * (see RI_PLAN_XXX constants at head of file)
2263 : * ----------
2264 : */
2265 : static void
2266 2473 : ri_BuildQueryKey(RI_QueryKey *key, const RI_ConstraintInfo *riinfo,
2267 : int32 constr_queryno)
2268 : {
2269 : /*
2270 : * Inherited constraints with a common ancestor can share ri_query_cache
2271 : * entries for all query types except RI_PLAN_CHECK_LOOKUPPK_FROM_PK.
2272 : * Except in that case, the query processes the other table involved in
2273 : * the FK constraint (i.e., not the table on which the trigger has been
2274 : * fired), and so it will be the same for all members of the inheritance
2275 : * tree. So we may use the root constraint's OID in the hash key, rather
2276 : * than the constraint's own OID. This avoids creating duplicate SPI
2277 : * plans, saving lots of work and memory when there are many partitions
2278 : * with similar FK constraints.
2279 : *
2280 : * (Note that we must still have a separate RI_ConstraintInfo for each
2281 : * constraint, because partitions can have different column orders,
2282 : * resulting in different pk_attnums[] or fk_attnums[] array contents.)
2283 : *
2284 : * We assume struct RI_QueryKey contains no padding bytes, else we'd need
2285 : * to use memset to clear them.
2286 : */
2287 2473 : if (constr_queryno != RI_PLAN_CHECK_LOOKUPPK_FROM_PK)
2288 1951 : key->constr_id = riinfo->constraint_root_id;
2289 : else
2290 522 : key->constr_id = riinfo->constraint_id;
2291 2473 : key->constr_queryno = constr_queryno;
2292 2473 : }
2293 :
2294 : /*
2295 : * Check that RI trigger function was called in expected context
2296 : */
2297 : static void
2298 605817 : ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname, int tgkind)
2299 : {
2300 605817 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
2301 :
2302 605817 : if (!CALLED_AS_TRIGGER(fcinfo))
2303 0 : ereport(ERROR,
2304 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2305 : errmsg("function \"%s\" was not called by trigger manager", funcname)));
2306 :
2307 : /*
2308 : * Check proper event
2309 : */
2310 605817 : if (!TRIGGER_FIRED_AFTER(trigdata->tg_event) ||
2311 605817 : !TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
2312 0 : ereport(ERROR,
2313 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2314 : errmsg("function \"%s\" must be fired AFTER ROW", funcname)));
2315 :
2316 605817 : switch (tgkind)
2317 : {
2318 604412 : case RI_TRIGTYPE_INSERT:
2319 604412 : if (!TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
2320 0 : ereport(ERROR,
2321 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2322 : errmsg("function \"%s\" must be fired for INSERT", funcname)));
2323 604412 : break;
2324 866 : case RI_TRIGTYPE_UPDATE:
2325 866 : if (!TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
2326 0 : ereport(ERROR,
2327 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2328 : errmsg("function \"%s\" must be fired for UPDATE", funcname)));
2329 866 : break;
2330 539 : case RI_TRIGTYPE_DELETE:
2331 539 : if (!TRIGGER_FIRED_BY_DELETE(trigdata->tg_event))
2332 0 : ereport(ERROR,
2333 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2334 : errmsg("function \"%s\" must be fired for DELETE", funcname)));
2335 539 : break;
2336 : }
2337 605817 : }
2338 :
2339 :
2340 : /*
2341 : * Fetch the RI_ConstraintInfo struct for the trigger's FK constraint.
2342 : */
2343 : static const RI_ConstraintInfo *
2344 608935 : ri_FetchConstraintInfo(Trigger *trigger, Relation trig_rel, bool rel_is_pk)
2345 : {
2346 608935 : Oid constraintOid = trigger->tgconstraint;
2347 : const RI_ConstraintInfo *riinfo;
2348 :
2349 : /*
2350 : * Check that the FK constraint's OID is available; it might not be if
2351 : * we've been invoked via an ordinary trigger or an old-style "constraint
2352 : * trigger".
2353 : */
2354 608935 : if (!OidIsValid(constraintOid))
2355 0 : ereport(ERROR,
2356 : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2357 : errmsg("no pg_constraint entry for trigger \"%s\" on table \"%s\"",
2358 : trigger->tgname, RelationGetRelationName(trig_rel)),
2359 : errhint("Remove this referential integrity trigger and its mates, then do ALTER TABLE ADD CONSTRAINT.")));
2360 :
2361 : /* Find or create a hashtable entry for the constraint */
2362 608935 : riinfo = ri_LoadConstraintInfo(constraintOid);
2363 :
2364 : /* Do some easy cross-checks against the trigger call data */
2365 608935 : if (rel_is_pk)
2366 : {
2367 2731 : if (riinfo->fk_relid != trigger->tgconstrrelid ||
2368 2731 : riinfo->pk_relid != RelationGetRelid(trig_rel))
2369 0 : elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
2370 : trigger->tgname, RelationGetRelationName(trig_rel));
2371 : }
2372 : else
2373 : {
2374 606204 : if (riinfo->fk_relid != RelationGetRelid(trig_rel) ||
2375 606204 : riinfo->pk_relid != trigger->tgconstrrelid)
2376 0 : elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
2377 : trigger->tgname, RelationGetRelationName(trig_rel));
2378 : }
2379 :
2380 608935 : if (riinfo->confmatchtype != FKCONSTR_MATCH_FULL &&
2381 608622 : riinfo->confmatchtype != FKCONSTR_MATCH_PARTIAL &&
2382 608622 : riinfo->confmatchtype != FKCONSTR_MATCH_SIMPLE)
2383 0 : elog(ERROR, "unrecognized confmatchtype: %d",
2384 : riinfo->confmatchtype);
2385 :
2386 608935 : if (riinfo->confmatchtype == FKCONSTR_MATCH_PARTIAL)
2387 0 : ereport(ERROR,
2388 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2389 : errmsg("MATCH PARTIAL not yet implemented")));
2390 :
2391 608935 : return riinfo;
2392 : }
2393 :
2394 : /*
2395 : * Fetch or create the RI_ConstraintInfo struct for an FK constraint.
2396 : */
2397 : static const RI_ConstraintInfo *
2398 611577 : ri_LoadConstraintInfo(Oid constraintOid)
2399 : {
2400 : RI_ConstraintInfo *riinfo;
2401 : bool found;
2402 : HeapTuple tup;
2403 : Form_pg_constraint conForm;
2404 :
2405 : /*
2406 : * On the first call initialize the hashtable
2407 : */
2408 611577 : if (!ri_constraint_cache)
2409 264 : ri_InitHashTables();
2410 :
2411 : /*
2412 : * Find or create a hash entry. If we find a valid one, just return it.
2413 : */
2414 611577 : riinfo = (RI_ConstraintInfo *) hash_search(ri_constraint_cache,
2415 : &constraintOid,
2416 : HASH_ENTER, &found);
2417 611577 : if (!found)
2418 2472 : riinfo->valid = false;
2419 609105 : else if (riinfo->valid)
2420 608840 : return riinfo;
2421 :
2422 : /*
2423 : * Fetch the pg_constraint row so we can fill in the entry.
2424 : */
2425 2737 : tup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constraintOid));
2426 2737 : if (!HeapTupleIsValid(tup)) /* should not happen */
2427 0 : elog(ERROR, "cache lookup failed for constraint %u", constraintOid);
2428 2737 : conForm = (Form_pg_constraint) GETSTRUCT(tup);
2429 :
2430 2737 : if (conForm->contype != CONSTRAINT_FOREIGN) /* should not happen */
2431 0 : elog(ERROR, "constraint %u is not a foreign key constraint",
2432 : constraintOid);
2433 :
2434 : /* And extract data */
2435 : Assert(riinfo->constraint_id == constraintOid);
2436 2737 : if (OidIsValid(conForm->conparentid))
2437 964 : riinfo->constraint_root_id =
2438 964 : get_ri_constraint_root(conForm->conparentid);
2439 : else
2440 1773 : riinfo->constraint_root_id = constraintOid;
2441 2737 : riinfo->oidHashValue = GetSysCacheHashValue1(CONSTROID,
2442 : ObjectIdGetDatum(constraintOid));
2443 2737 : riinfo->rootHashValue = GetSysCacheHashValue1(CONSTROID,
2444 : ObjectIdGetDatum(riinfo->constraint_root_id));
2445 2737 : memcpy(&riinfo->conname, &conForm->conname, sizeof(NameData));
2446 2737 : riinfo->pk_relid = conForm->confrelid;
2447 2737 : riinfo->fk_relid = conForm->conrelid;
2448 2737 : riinfo->confupdtype = conForm->confupdtype;
2449 2737 : riinfo->confdeltype = conForm->confdeltype;
2450 2737 : riinfo->confmatchtype = conForm->confmatchtype;
2451 2737 : riinfo->hasperiod = conForm->conperiod;
2452 :
2453 2737 : DeconstructFkConstraintRow(tup,
2454 : &riinfo->nkeys,
2455 2737 : riinfo->fk_attnums,
2456 2737 : riinfo->pk_attnums,
2457 2737 : riinfo->pf_eq_oprs,
2458 2737 : riinfo->pp_eq_oprs,
2459 2737 : riinfo->ff_eq_oprs,
2460 : &riinfo->ndelsetcols,
2461 2737 : riinfo->confdelsetcols);
2462 :
2463 : /*
2464 : * For temporal FKs, get the operators and functions we need. We ask the
2465 : * opclass of the PK element for these. This all gets cached (as does the
2466 : * generated plan), so there's no performance issue.
2467 : */
2468 2737 : if (riinfo->hasperiod)
2469 : {
2470 141 : Oid opclass = get_index_column_opclass(conForm->conindid, riinfo->nkeys);
2471 :
2472 141 : FindFKPeriodOpers(opclass,
2473 : &riinfo->period_contained_by_oper,
2474 : &riinfo->agged_period_contained_by_oper,
2475 : &riinfo->period_intersect_oper);
2476 : }
2477 :
2478 : /* Metadata used by fast path. */
2479 2737 : riinfo->conindid = conForm->conindid;
2480 2737 : riinfo->pk_is_partitioned =
2481 2737 : (get_rel_relkind(riinfo->pk_relid) == RELKIND_PARTITIONED_TABLE);
2482 :
2483 2737 : ReleaseSysCache(tup);
2484 :
2485 : /*
2486 : * For efficient processing of invalidation messages below, we keep a
2487 : * doubly-linked count list of all currently valid entries.
2488 : */
2489 2737 : dclist_push_tail(&ri_constraint_cache_valid_list, &riinfo->valid_link);
2490 :
2491 2737 : riinfo->valid = true;
2492 :
2493 2737 : riinfo->fpmeta = NULL;
2494 :
2495 2737 : return riinfo;
2496 : }
2497 :
2498 : /*
2499 : * get_ri_constraint_root
2500 : * Returns the OID of the constraint's root parent
2501 : */
2502 : static Oid
2503 964 : get_ri_constraint_root(Oid constrOid)
2504 : {
2505 : for (;;)
2506 232 : {
2507 : HeapTuple tuple;
2508 : Oid constrParentOid;
2509 :
2510 1196 : tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constrOid));
2511 1196 : if (!HeapTupleIsValid(tuple))
2512 0 : elog(ERROR, "cache lookup failed for constraint %u", constrOid);
2513 1196 : constrParentOid = ((Form_pg_constraint) GETSTRUCT(tuple))->conparentid;
2514 1196 : ReleaseSysCache(tuple);
2515 1196 : if (!OidIsValid(constrParentOid))
2516 964 : break; /* we reached the root constraint */
2517 232 : constrOid = constrParentOid;
2518 : }
2519 964 : return constrOid;
2520 : }
2521 :
2522 : /*
2523 : * Callback for pg_constraint inval events
2524 : *
2525 : * While most syscache callbacks just flush all their entries, pg_constraint
2526 : * gets enough update traffic that it's probably worth being smarter.
2527 : * Invalidate any ri_constraint_cache entry associated with the syscache
2528 : * entry with the specified hash value, or all entries if hashvalue == 0.
2529 : *
2530 : * Note: at the time a cache invalidation message is processed there may be
2531 : * active references to the cache. Because of this we never remove entries
2532 : * from the cache, but only mark them invalid, which is harmless to active
2533 : * uses. (Any query using an entry should hold a lock sufficient to keep that
2534 : * data from changing under it --- but we may get cache flushes anyway.)
2535 : */
2536 : static void
2537 58127 : InvalidateConstraintCacheCallBack(Datum arg, SysCacheIdentifier cacheid,
2538 : uint32 hashvalue)
2539 : {
2540 : dlist_mutable_iter iter;
2541 :
2542 : Assert(ri_constraint_cache != NULL);
2543 :
2544 : /*
2545 : * If the list of currently valid entries gets excessively large, we mark
2546 : * them all invalid so we can empty the list. This arrangement avoids
2547 : * O(N^2) behavior in situations where a session touches many foreign keys
2548 : * and also does many ALTER TABLEs, such as a restore from pg_dump.
2549 : */
2550 58127 : if (dclist_count(&ri_constraint_cache_valid_list) > 1000)
2551 0 : hashvalue = 0; /* pretend it's a cache reset */
2552 :
2553 242780 : dclist_foreach_modify(iter, &ri_constraint_cache_valid_list)
2554 : {
2555 184653 : RI_ConstraintInfo *riinfo = dclist_container(RI_ConstraintInfo,
2556 : valid_link, iter.cur);
2557 :
2558 : /*
2559 : * We must invalidate not only entries directly matching the given
2560 : * hash value, but also child entries, in case the invalidation
2561 : * affects a root constraint.
2562 : */
2563 184653 : if (hashvalue == 0 ||
2564 184609 : riinfo->oidHashValue == hashvalue ||
2565 182889 : riinfo->rootHashValue == hashvalue)
2566 : {
2567 1980 : riinfo->valid = false;
2568 1980 : if (riinfo->fpmeta)
2569 : {
2570 640 : pfree(riinfo->fpmeta);
2571 640 : riinfo->fpmeta = NULL;
2572 : }
2573 : /* Remove invalidated entries from the list, too */
2574 1980 : dclist_delete_from(&ri_constraint_cache_valid_list, iter.cur);
2575 : }
2576 : }
2577 58127 : }
2578 :
2579 :
2580 : /*
2581 : * Prepare execution plan for a query to enforce an RI restriction
2582 : */
2583 : static SPIPlanPtr
2584 1166 : ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
2585 : RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel)
2586 : {
2587 : SPIPlanPtr qplan;
2588 : Relation query_rel;
2589 : Oid save_userid;
2590 : int save_sec_context;
2591 :
2592 : /*
2593 : * Use the query type code to determine whether the query is run against
2594 : * the PK or FK table; we'll do the check as that table's owner
2595 : */
2596 1166 : if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
2597 614 : query_rel = pk_rel;
2598 : else
2599 552 : query_rel = fk_rel;
2600 :
2601 : /* Switch to proper UID to perform check as */
2602 1166 : GetUserIdAndSecContext(&save_userid, &save_sec_context);
2603 1166 : SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
2604 : save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
2605 : SECURITY_NOFORCE_RLS);
2606 :
2607 : /* Create the plan */
2608 1166 : qplan = SPI_prepare(querystr, nargs, argtypes);
2609 :
2610 1166 : if (qplan == NULL)
2611 0 : elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), querystr);
2612 :
2613 : /* Restore UID and security context */
2614 1166 : SetUserIdAndSecContext(save_userid, save_sec_context);
2615 :
2616 : /* Save the plan */
2617 1166 : SPI_keepplan(qplan);
2618 1166 : ri_HashPreparedPlan(qkey, qplan);
2619 :
2620 1166 : return qplan;
2621 : }
2622 :
2623 : /*
2624 : * Perform a query to enforce an RI restriction
2625 : */
2626 : static bool
2627 2473 : ri_PerformCheck(const RI_ConstraintInfo *riinfo,
2628 : RI_QueryKey *qkey, SPIPlanPtr qplan,
2629 : Relation fk_rel, Relation pk_rel,
2630 : TupleTableSlot *oldslot, TupleTableSlot *newslot,
2631 : bool is_restrict,
2632 : bool detectNewRows, int expect_OK)
2633 : {
2634 : Relation query_rel,
2635 : source_rel;
2636 : bool source_is_pk;
2637 : Snapshot test_snapshot;
2638 : Snapshot crosscheck_snapshot;
2639 : int limit;
2640 : int spi_result;
2641 : Oid save_userid;
2642 : int save_sec_context;
2643 : Datum vals[RI_MAX_NUMKEYS * 2];
2644 : char nulls[RI_MAX_NUMKEYS * 2];
2645 :
2646 : /*
2647 : * Use the query type code to determine whether the query is run against
2648 : * the PK or FK table; we'll do the check as that table's owner
2649 : */
2650 2473 : if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
2651 1312 : query_rel = pk_rel;
2652 : else
2653 1161 : query_rel = fk_rel;
2654 :
2655 : /*
2656 : * The values for the query are taken from the table on which the trigger
2657 : * is called - it is normally the other one with respect to query_rel. An
2658 : * exception is ri_Check_Pk_Match(), which uses the PK table for both (and
2659 : * sets queryno to RI_PLAN_CHECK_LOOKUPPK_FROM_PK). We might eventually
2660 : * need some less klugy way to determine this.
2661 : */
2662 2473 : if (qkey->constr_queryno == RI_PLAN_CHECK_LOOKUPPK)
2663 : {
2664 790 : source_rel = fk_rel;
2665 790 : source_is_pk = false;
2666 : }
2667 : else
2668 : {
2669 1683 : source_rel = pk_rel;
2670 1683 : source_is_pk = true;
2671 : }
2672 :
2673 : /* Extract the parameters to be passed into the query */
2674 2473 : if (newslot)
2675 : {
2676 934 : ri_ExtractValues(source_rel, newslot, riinfo, source_is_pk,
2677 : vals, nulls);
2678 934 : if (oldslot)
2679 144 : ri_ExtractValues(source_rel, oldslot, riinfo, source_is_pk,
2680 144 : vals + riinfo->nkeys, nulls + riinfo->nkeys);
2681 : }
2682 : else
2683 : {
2684 1539 : ri_ExtractValues(source_rel, oldslot, riinfo, source_is_pk,
2685 : vals, nulls);
2686 : }
2687 :
2688 : /*
2689 : * In READ COMMITTED mode, we just need to use an up-to-date regular
2690 : * snapshot, and we will see all rows that could be interesting. But in
2691 : * transaction-snapshot mode, we can't change the transaction snapshot. If
2692 : * the caller passes detectNewRows == false then it's okay to do the query
2693 : * with the transaction snapshot; otherwise we use a current snapshot, and
2694 : * tell the executor to error out if it finds any rows under the current
2695 : * snapshot that wouldn't be visible per the transaction snapshot. Note
2696 : * that SPI_execute_snapshot will register the snapshots, so we don't need
2697 : * to bother here.
2698 : */
2699 2473 : if (IsolationUsesXactSnapshot() && detectNewRows)
2700 : {
2701 36 : CommandCounterIncrement(); /* be sure all my own work is visible */
2702 36 : test_snapshot = GetLatestSnapshot();
2703 36 : crosscheck_snapshot = GetTransactionSnapshot();
2704 : }
2705 : else
2706 : {
2707 : /* the default SPI behavior is okay */
2708 2437 : test_snapshot = InvalidSnapshot;
2709 2437 : crosscheck_snapshot = InvalidSnapshot;
2710 : }
2711 :
2712 : /*
2713 : * If this is a select query (e.g., for a 'no action' or 'restrict'
2714 : * trigger), we only need to see if there is a single row in the table,
2715 : * matching the key. Otherwise, limit = 0 - because we want the query to
2716 : * affect ALL the matching rows.
2717 : */
2718 2473 : limit = (expect_OK == SPI_OK_SELECT) ? 1 : 0;
2719 :
2720 : /* Switch to proper UID to perform check as */
2721 2473 : GetUserIdAndSecContext(&save_userid, &save_sec_context);
2722 2473 : SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
2723 : save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
2724 : SECURITY_NOFORCE_RLS);
2725 :
2726 : /*
2727 : * Finally we can run the query.
2728 : *
2729 : * Set fire_triggers to false to ensure that AFTER triggers are queued in
2730 : * the outer query's after-trigger context and fire after all RI updates
2731 : * on the same row are complete, rather than immediately.
2732 : */
2733 2473 : spi_result = SPI_execute_snapshot(qplan,
2734 : vals, nulls,
2735 : test_snapshot, crosscheck_snapshot,
2736 : false, false, limit);
2737 :
2738 : /* Restore UID and security context */
2739 2463 : SetUserIdAndSecContext(save_userid, save_sec_context);
2740 :
2741 : /* Check result */
2742 2463 : if (spi_result < 0)
2743 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
2744 :
2745 2463 : if (expect_OK >= 0 && spi_result != expect_OK)
2746 0 : ereport(ERROR,
2747 : (errcode(ERRCODE_INTERNAL_ERROR),
2748 : errmsg("referential integrity query on \"%s\" from constraint \"%s\" on \"%s\" gave unexpected result",
2749 : RelationGetRelationName(pk_rel),
2750 : NameStr(riinfo->conname),
2751 : RelationGetRelationName(fk_rel)),
2752 : errhint("This is most likely due to a rule having rewritten the query.")));
2753 :
2754 : /* XXX wouldn't it be clearer to do this part at the caller? */
2755 2463 : if (qkey->constr_queryno != RI_PLAN_CHECK_LOOKUPPK_FROM_PK &&
2756 1528 : expect_OK == SPI_OK_SELECT &&
2757 1528 : (SPI_processed == 0) == (qkey->constr_queryno == RI_PLAN_CHECK_LOOKUPPK))
2758 462 : ri_ReportViolation(riinfo,
2759 : pk_rel, fk_rel,
2760 : newslot ? newslot : oldslot,
2761 : NULL,
2762 : qkey->constr_queryno, is_restrict, false);
2763 :
2764 2001 : return SPI_processed != 0;
2765 : }
2766 :
2767 : /*
2768 : * ri_FastPathCheck
2769 : * Perform per row FK existence check via direct index probe,
2770 : * bypassing SPI.
2771 : *
2772 : * If no matching PK row exists, report the violation via ri_ReportViolation(),
2773 : * otherwise, the function returns normally.
2774 : *
2775 : * Note: This is only used by the ALTER TABLE validation path. Other paths use
2776 : * ri_FastPathBatchAdd().
2777 : */
2778 : static void
2779 44 : ri_FastPathCheck(const RI_ConstraintInfo *riinfo,
2780 : Relation fk_rel, TupleTableSlot *newslot)
2781 : {
2782 : Relation pk_rel;
2783 : Relation idx_rel;
2784 : IndexScanDesc scandesc;
2785 : TupleTableSlot *slot;
2786 : Datum pk_vals[INDEX_MAX_KEYS];
2787 : char pk_nulls[INDEX_MAX_KEYS];
2788 : ScanKeyData skey[INDEX_MAX_KEYS];
2789 44 : bool found = false;
2790 : Oid saved_userid;
2791 : int saved_sec_context;
2792 : Snapshot snapshot;
2793 :
2794 : /*
2795 : * Advance the command counter so the snapshot sees the effects of prior
2796 : * triggers in this statement. Mirrors what the SPI path does in
2797 : * ri_PerformCheck().
2798 : */
2799 44 : CommandCounterIncrement();
2800 44 : snapshot = RegisterSnapshot(GetTransactionSnapshot());
2801 :
2802 44 : pk_rel = table_open(riinfo->pk_relid, RowShareLock);
2803 44 : idx_rel = index_open(riinfo->conindid, AccessShareLock);
2804 :
2805 44 : slot = table_slot_create(pk_rel, NULL);
2806 44 : scandesc = index_beginscan(pk_rel, idx_rel,
2807 : snapshot, NULL,
2808 44 : riinfo->nkeys, 0,
2809 : SO_NONE);
2810 :
2811 44 : GetUserIdAndSecContext(&saved_userid, &saved_sec_context);
2812 44 : SetUserIdAndSecContext(RelationGetForm(pk_rel)->relowner,
2813 : saved_sec_context |
2814 : SECURITY_LOCAL_USERID_CHANGE |
2815 : SECURITY_NOFORCE_RLS);
2816 44 : ri_CheckPermissions(pk_rel);
2817 :
2818 44 : if (riinfo->fpmeta == NULL)
2819 : {
2820 : /* Reload to ensure it's valid. */
2821 8 : riinfo = ri_LoadConstraintInfo(riinfo->constraint_id);
2822 8 : ri_populate_fastpath_metadata((RI_ConstraintInfo *) riinfo,
2823 : fk_rel, idx_rel);
2824 : }
2825 : Assert(riinfo->fpmeta);
2826 44 : ri_ExtractValues(fk_rel, newslot, riinfo, false, pk_vals, pk_nulls);
2827 44 : build_index_scankeys(riinfo, idx_rel, pk_vals, pk_nulls, skey);
2828 44 : found = ri_FastPathProbeOne(pk_rel, idx_rel, scandesc, slot,
2829 44 : snapshot, riinfo, skey, riinfo->nkeys);
2830 44 : SetUserIdAndSecContext(saved_userid, saved_sec_context);
2831 44 : index_endscan(scandesc);
2832 44 : ExecDropSingleTupleTableSlot(slot);
2833 44 : UnregisterSnapshot(snapshot);
2834 :
2835 44 : if (!found)
2836 4 : ri_ReportViolation(riinfo, pk_rel, fk_rel,
2837 : newslot, NULL,
2838 : RI_PLAN_CHECK_LOOKUPPK, false, false);
2839 :
2840 40 : index_close(idx_rel, NoLock);
2841 40 : table_close(pk_rel, NoLock);
2842 40 : }
2843 :
2844 : /*
2845 : * ri_FastPathBatchAdd
2846 : * Buffer a FK row for batched probing.
2847 : *
2848 : * Adds the row to the batch buffer. When the buffer is full, flushes all
2849 : * buffered rows by probing the PK index. Any violation is reported
2850 : * immediately during the flush via ri_ReportViolation (which does not return).
2851 : *
2852 : * Uses the per-batch cache (RI_FastPathEntry) to avoid per-row relation
2853 : * open/close, slot creation, etc.
2854 : *
2855 : * The batch is also flushed at end of trigger-firing cycle via
2856 : * ri_FastPathEndBatch().
2857 : */
2858 : static void
2859 603630 : ri_FastPathBatchAdd(const RI_ConstraintInfo *riinfo,
2860 : Relation fk_rel, TupleTableSlot *newslot)
2861 : {
2862 603630 : RI_FastPathEntry *fpentry = ri_FastPathGetEntry(riinfo, fk_rel);
2863 : MemoryContext oldcxt;
2864 :
2865 603630 : oldcxt = MemoryContextSwitchTo(fpentry->flush_cxt);
2866 1207260 : fpentry->batch[fpentry->batch_count] =
2867 603630 : ExecCopySlotHeapTuple(newslot);
2868 603630 : fpentry->batch_count++;
2869 603630 : MemoryContextSwitchTo(oldcxt);
2870 :
2871 603630 : if (fpentry->batch_count >= RI_FASTPATH_BATCH_SIZE)
2872 9392 : ri_FastPathBatchFlush(fpentry, fk_rel, riinfo);
2873 603630 : }
2874 :
2875 : /*
2876 : * ri_FastPathBatchFlush
2877 : * Flush all buffered FK rows by probing the PK index.
2878 : *
2879 : * Dispatches to ri_FastPathFlushArray() for single-column FKs
2880 : * (using SK_SEARCHARRAY) or ri_FastPathFlushLoop() for multi-column
2881 : * FKs (per-row probing). Violations are reported immediately via
2882 : * ri_ReportViolation(), which does not return.
2883 : */
2884 : static void
2885 11091 : ri_FastPathBatchFlush(RI_FastPathEntry *fpentry, Relation fk_rel,
2886 : const RI_ConstraintInfo *riinfo)
2887 : {
2888 11091 : Relation pk_rel = fpentry->pk_rel;
2889 11091 : Relation idx_rel = fpentry->idx_rel;
2890 11091 : TupleTableSlot *fk_slot = fpentry->fk_slot;
2891 : Snapshot snapshot;
2892 : IndexScanDesc scandesc;
2893 : Oid saved_userid;
2894 : int saved_sec_context;
2895 : MemoryContext oldcxt;
2896 : int violation_index;
2897 :
2898 11091 : if (fpentry->batch_count == 0)
2899 0 : return;
2900 :
2901 : /*
2902 : * CCI and security context switch are done once for the entire batch.
2903 : * Per-row CCI is unnecessary because by the time a flush runs, all AFTER
2904 : * triggers for the buffered rows have already fired (trigger invocations
2905 : * strictly alternate per row), so a single CCI advances past all their
2906 : * effects. Per-row security context switch is unnecessary because each
2907 : * row's probe runs entirely as the PK table owner, same as the SPI path
2908 : * -- the only difference is that the SPI path sets and restores the
2909 : * context per row whereas we do it once around the whole batch.
2910 : */
2911 11091 : CommandCounterIncrement();
2912 11091 : snapshot = RegisterSnapshot(GetTransactionSnapshot());
2913 :
2914 : /*
2915 : * build_index_scankeys() may palloc cast results for cross-type FKs. Use
2916 : * the entry's short-lived flush context so these don't accumulate across
2917 : * batches.
2918 : */
2919 11091 : oldcxt = MemoryContextSwitchTo(fpentry->flush_cxt);
2920 :
2921 11091 : scandesc = index_beginscan(pk_rel, idx_rel, snapshot, NULL,
2922 11091 : riinfo->nkeys, 0, SO_NONE);
2923 :
2924 11091 : GetUserIdAndSecContext(&saved_userid, &saved_sec_context);
2925 11091 : SetUserIdAndSecContext(RelationGetForm(pk_rel)->relowner,
2926 : saved_sec_context |
2927 : SECURITY_LOCAL_USERID_CHANGE |
2928 : SECURITY_NOFORCE_RLS);
2929 :
2930 : /*
2931 : * Check that the current user has permission to access pk_rel. Done here
2932 : * rather than at entry creation so that permission changes between
2933 : * flushes are respected, matching the per-row behavior of the SPI path,
2934 : * albeit checked once per flush rather than once per row, like in
2935 : * ri_FastPathCheck().
2936 : */
2937 11091 : ri_CheckPermissions(pk_rel);
2938 :
2939 11087 : if (riinfo->fpmeta == NULL)
2940 : {
2941 : /* Reload to ensure it's valid. */
2942 935 : riinfo = ri_LoadConstraintInfo(riinfo->constraint_id);
2943 935 : ri_populate_fastpath_metadata((RI_ConstraintInfo *) riinfo,
2944 : fk_rel, idx_rel);
2945 : }
2946 : Assert(riinfo->fpmeta);
2947 :
2948 : /* Skip array overhead for single-row batches. */
2949 11087 : if (riinfo->nkeys == 1 && fpentry->batch_count > 1)
2950 9533 : violation_index = ri_FastPathFlushArray(fpentry, fk_slot, riinfo,
2951 : fk_rel, snapshot, scandesc);
2952 : else
2953 1554 : violation_index = ri_FastPathFlushLoop(fpentry, fk_slot, riinfo,
2954 : fk_rel, snapshot, scandesc);
2955 :
2956 11081 : SetUserIdAndSecContext(saved_userid, saved_sec_context);
2957 11081 : UnregisterSnapshot(snapshot);
2958 11081 : index_endscan(scandesc);
2959 :
2960 11081 : if (violation_index >= 0)
2961 : {
2962 274 : ExecStoreHeapTuple(fpentry->batch[violation_index], fk_slot, false);
2963 274 : ri_ReportViolation(riinfo, pk_rel, fk_rel,
2964 : fk_slot, NULL,
2965 : RI_PLAN_CHECK_LOOKUPPK, false, false);
2966 : }
2967 :
2968 10807 : MemoryContextReset(fpentry->flush_cxt);
2969 10807 : MemoryContextSwitchTo(oldcxt);
2970 :
2971 : /* Reset. */
2972 10807 : fpentry->batch_count = 0;
2973 : }
2974 :
2975 : /*
2976 : * ri_FastPathFlushLoop
2977 : * Multi-column fallback: probe the index once per buffered row.
2978 : *
2979 : * Used for composite foreign keys where SK_SEARCHARRAY does not
2980 : * apply, and also for single-row batches of single-column FKs where
2981 : * the array overhead is not worth it.
2982 : *
2983 : * Returns the index of the first violating row in the batch array, or -1 if
2984 : * all rows are valid.
2985 : */
2986 : static int
2987 1554 : ri_FastPathFlushLoop(RI_FastPathEntry *fpentry, TupleTableSlot *fk_slot,
2988 : const RI_ConstraintInfo *riinfo, Relation fk_rel,
2989 : Snapshot snapshot, IndexScanDesc scandesc)
2990 : {
2991 1554 : Relation pk_rel = fpentry->pk_rel;
2992 1554 : Relation idx_rel = fpentry->idx_rel;
2993 1554 : TupleTableSlot *pk_slot = fpentry->pk_slot;
2994 : Datum pk_vals[INDEX_MAX_KEYS];
2995 : char pk_nulls[INDEX_MAX_KEYS];
2996 : ScanKeyData skey[INDEX_MAX_KEYS];
2997 1554 : bool found = true;
2998 :
2999 3224 : for (int i = 0; i < fpentry->batch_count; i++)
3000 : {
3001 1946 : ExecStoreHeapTuple(fpentry->batch[i], fk_slot, false);
3002 1946 : ri_ExtractValues(fk_rel, fk_slot, riinfo, false, pk_vals, pk_nulls);
3003 1946 : build_index_scankeys(riinfo, idx_rel, pk_vals, pk_nulls, skey);
3004 :
3005 1946 : found = ri_FastPathProbeOne(pk_rel, idx_rel, scandesc, pk_slot,
3006 1946 : snapshot, riinfo, skey, riinfo->nkeys);
3007 :
3008 : /* Report first unmatched row */
3009 1940 : if (!found)
3010 270 : return i;
3011 : }
3012 :
3013 : /* All pass. */
3014 1278 : return -1;
3015 : }
3016 :
3017 : /*
3018 : * ri_FastPathFlushArray
3019 : * Single-column fast path using SK_SEARCHARRAY.
3020 : *
3021 : * Builds an array of FK values and does one index scan with
3022 : * SK_SEARCHARRAY. The index AM sorts and deduplicates the array
3023 : * internally, then walks matching leaf pages in order. Each
3024 : * matched PK tuple is locked and rechecked as before; a matched[]
3025 : * bitmap tracks which batch items were satisfied.
3026 : *
3027 : * Returns the index of the first violating row in the batch array, or -1 if
3028 : * all rows are valid.
3029 : */
3030 : static int
3031 9533 : ri_FastPathFlushArray(RI_FastPathEntry *fpentry, TupleTableSlot *fk_slot,
3032 : const RI_ConstraintInfo *riinfo, Relation fk_rel,
3033 : Snapshot snapshot, IndexScanDesc scandesc)
3034 : {
3035 9533 : FastPathMeta *fpmeta = riinfo->fpmeta;
3036 9533 : Relation pk_rel = fpentry->pk_rel;
3037 9533 : Relation idx_rel = fpentry->idx_rel;
3038 9533 : TupleTableSlot *pk_slot = fpentry->pk_slot;
3039 : Datum search_vals[RI_FASTPATH_BATCH_SIZE];
3040 : bool matched[RI_FASTPATH_BATCH_SIZE];
3041 9533 : int nvals = fpentry->batch_count;
3042 : Datum pk_vals[INDEX_MAX_KEYS];
3043 : char pk_nulls[INDEX_MAX_KEYS];
3044 : ScanKeyData skey[1];
3045 : FmgrInfo *cast_func_finfo;
3046 : FmgrInfo *eq_opr_finfo;
3047 : Oid elem_type;
3048 : int16 elem_len;
3049 : bool elem_byval;
3050 : char elem_align;
3051 : ArrayType *arr;
3052 :
3053 : Assert(fpmeta);
3054 :
3055 9533 : memset(matched, 0, nvals * sizeof(bool));
3056 :
3057 : /*
3058 : * Extract FK values, casting to the operator's expected input type if
3059 : * needed (e.g. int8 FK -> int4 for int48eq).
3060 : */
3061 9533 : cast_func_finfo = &fpmeta->cast_func_finfo[0];
3062 9533 : eq_opr_finfo = &fpmeta->eq_opr_finfo[0];
3063 611202 : for (int i = 0; i < nvals; i++)
3064 : {
3065 601669 : ExecStoreHeapTuple(fpentry->batch[i], fk_slot, false);
3066 601669 : ri_ExtractValues(fk_rel, fk_slot, riinfo, false, pk_vals, pk_nulls);
3067 :
3068 : /* Cast if needed (e.g. int8 FK -> numeric PK) */
3069 601669 : if (OidIsValid(cast_func_finfo->fn_oid))
3070 0 : search_vals[i] = FunctionCall3(cast_func_finfo,
3071 : pk_vals[0],
3072 : Int32GetDatum(-1),
3073 : BoolGetDatum(false));
3074 : else
3075 601669 : search_vals[i] = pk_vals[0];
3076 : }
3077 :
3078 : /*
3079 : * Array element type must match the operator's right-hand input type,
3080 : * which is what the index comparison expects on the search side.
3081 : * ri_populate_fastpath_metadata() stores exactly this via
3082 : * get_op_opfamily_properties(), which returns the operator's right-hand
3083 : * type as the subtype for cross-type operators (e.g. int8 for int48eq)
3084 : * and the common type for same-type operators.
3085 : */
3086 9533 : elem_type = fpmeta->subtypes[0];
3087 : Assert(OidIsValid(elem_type));
3088 9533 : get_typlenbyvalalign(elem_type, &elem_len, &elem_byval, &elem_align);
3089 :
3090 9533 : arr = construct_array(search_vals, nvals,
3091 : elem_type, elem_len, elem_byval, elem_align);
3092 :
3093 : /*
3094 : * Build scan key with SK_SEARCHARRAY. The index AM code will internally
3095 : * sort and deduplicate, then walk leaf pages in order.
3096 : *
3097 : * PK indexes are always btree, which supports SK_SEARCHARRAY.
3098 : */
3099 : Assert(idx_rel->rd_indam->amsearcharray);
3100 9533 : ScanKeyEntryInitialize(&skey[0],
3101 : SK_SEARCHARRAY,
3102 : 1, /* attno */
3103 9533 : fpmeta->strats[0],
3104 : fpmeta->subtypes[0],
3105 9533 : idx_rel->rd_indcollation[0],
3106 : fpmeta->regops[0],
3107 : PointerGetDatum(arr));
3108 :
3109 9533 : index_rescan(scandesc, skey, 1, NULL, 0);
3110 :
3111 : /*
3112 : * Walk all matches. The index AM returns them in index order. For each
3113 : * match, find which batch item(s) it satisfies.
3114 : */
3115 420040 : while (index_getnext_slot(scandesc, ForwardScanDirection, pk_slot))
3116 : {
3117 : Datum found_val;
3118 : bool found_null;
3119 : bool concurrently_updated;
3120 : ScanKeyData recheck_skey[1];
3121 :
3122 410507 : if (!ri_LockPKTuple(pk_rel, pk_slot, snapshot, &concurrently_updated))
3123 0 : continue;
3124 :
3125 : /* Extract the PK value from the matched and locked tuple */
3126 410507 : found_val = slot_getattr(pk_slot, riinfo->pk_attnums[0], &found_null);
3127 : Assert(!found_null);
3128 :
3129 410507 : if (concurrently_updated)
3130 : {
3131 : /*
3132 : * Build a single-key scankey for recheck. We need the actual PK
3133 : * value that was found, not the FK search value.
3134 : */
3135 0 : ScanKeyEntryInitialize(&recheck_skey[0], 0, 1,
3136 0 : fpmeta->strats[0],
3137 : fpmeta->subtypes[0],
3138 0 : idx_rel->rd_indcollation[0],
3139 : fpmeta->regops[0],
3140 : found_val);
3141 0 : if (!recheck_matched_pk_tuple(idx_rel, recheck_skey, pk_slot))
3142 0 : continue;
3143 : }
3144 :
3145 : /*
3146 : * Linear scan to mark all batch items matching this PK value.
3147 : * O(batch_size) per match, O(batch_size^2) worst case -- fine for the
3148 : * current batch size of 64.
3149 : */
3150 26657840 : for (int i = 0; i < nvals; i++)
3151 : {
3152 39671800 : if (!matched[i] &&
3153 13424467 : DatumGetBool(FunctionCall2Coll(eq_opr_finfo,
3154 13424467 : idx_rel->rd_indcollation[0],
3155 : found_val,
3156 : search_vals[i])))
3157 601665 : matched[i] = true;
3158 : }
3159 : }
3160 :
3161 : /* Report first unmatched row */
3162 611198 : for (int i = 0; i < nvals; i++)
3163 601669 : if (!matched[i])
3164 4 : return i;
3165 :
3166 : /* All pass. */
3167 9529 : return -1;
3168 : }
3169 :
3170 : /*
3171 : * ri_FastPathProbeOne
3172 : * Probe the PK index for one set of scan keys, lock the matching
3173 : * tuple
3174 : *
3175 : * Returns true if a matching PK row was found, locked, and (if
3176 : * applicable) visible to the transaction snapshot.
3177 : */
3178 : static bool
3179 1990 : ri_FastPathProbeOne(Relation pk_rel, Relation idx_rel,
3180 : IndexScanDesc scandesc, TupleTableSlot *slot,
3181 : Snapshot snapshot, const RI_ConstraintInfo *riinfo,
3182 : ScanKeyData *skey, int nkeys)
3183 : {
3184 1990 : bool found = false;
3185 :
3186 1990 : index_rescan(scandesc, skey, nkeys, NULL, 0);
3187 :
3188 1990 : if (index_getnext_slot(scandesc, ForwardScanDirection, slot))
3189 : {
3190 : bool concurrently_updated;
3191 :
3192 1718 : if (ri_LockPKTuple(pk_rel, slot, snapshot,
3193 : &concurrently_updated))
3194 : {
3195 1711 : if (concurrently_updated)
3196 2 : found = recheck_matched_pk_tuple(idx_rel, skey, slot);
3197 : else
3198 1709 : found = true;
3199 : }
3200 : }
3201 :
3202 1984 : return found;
3203 : }
3204 :
3205 : /*
3206 : * ri_LockPKTuple
3207 : * Lock a PK tuple found by the fast-path index scan.
3208 : *
3209 : * Calls table_tuple_lock() directly with handling specific to RI checks.
3210 : * Returns true if the tuple was successfully locked.
3211 : *
3212 : * Sets *concurrently_updated to true if the locked tuple was reached
3213 : * by following an update chain (tmfd.traversed), indicating the caller
3214 : * should recheck the key.
3215 : */
3216 : static bool
3217 412225 : ri_LockPKTuple(Relation pk_rel, TupleTableSlot *slot, Snapshot snap,
3218 : bool *concurrently_updated)
3219 : {
3220 : TM_FailureData tmfd;
3221 : TM_Result result;
3222 412225 : int lockflags = TUPLE_LOCK_FLAG_LOCK_UPDATE_IN_PROGRESS;
3223 :
3224 412225 : *concurrently_updated = false;
3225 :
3226 412225 : if (!IsolationUsesXactSnapshot())
3227 412204 : lockflags |= TUPLE_LOCK_FLAG_FIND_LAST_VERSION;
3228 :
3229 412225 : result = table_tuple_lock(pk_rel, &slot->tts_tid, snap,
3230 : slot, GetCurrentCommandId(false),
3231 : LockTupleKeyShare, LockWaitBlock,
3232 : lockflags, &tmfd);
3233 :
3234 412222 : switch (result)
3235 : {
3236 412218 : case TM_Ok:
3237 412218 : if (tmfd.traversed)
3238 2 : *concurrently_updated = true;
3239 412218 : return true;
3240 :
3241 3 : case TM_Deleted:
3242 3 : if (IsolationUsesXactSnapshot())
3243 2 : ereport(ERROR,
3244 : (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
3245 : errmsg("could not serialize access due to concurrent update")));
3246 1 : return false;
3247 :
3248 1 : case TM_Updated:
3249 1 : if (IsolationUsesXactSnapshot())
3250 1 : ereport(ERROR,
3251 : (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
3252 : errmsg("could not serialize access due to concurrent update")));
3253 :
3254 : /*
3255 : * In READ COMMITTED, FIND_LAST_VERSION should have chased the
3256 : * chain and returned TM_Ok. Getting here means something
3257 : * unexpected -- fall through to error.
3258 : */
3259 0 : elog(ERROR, "unexpected table_tuple_lock status: %u", result);
3260 : break;
3261 :
3262 0 : case TM_SelfModified:
3263 :
3264 : /*
3265 : * The current command or a later command in this transaction
3266 : * modified the PK row. This shouldn't normally happen during an
3267 : * FK check (we're not modifying pk_rel), but handle it safely by
3268 : * treating the tuple as not found.
3269 : */
3270 0 : return false;
3271 :
3272 0 : case TM_Invisible:
3273 0 : elog(ERROR, "attempted to lock invisible tuple");
3274 : break;
3275 :
3276 0 : default:
3277 0 : elog(ERROR, "unrecognized table_tuple_lock status: %u", result);
3278 : break;
3279 : }
3280 :
3281 : return false; /* keep compiler quiet */
3282 : }
3283 :
3284 : static bool
3285 604464 : ri_fastpath_is_applicable(const RI_ConstraintInfo *riinfo)
3286 : {
3287 : /*
3288 : * Partitioned referenced tables are skipped for simplicity, since they
3289 : * require routing the probe through the correct partition using
3290 : * PartitionDirectory.
3291 : */
3292 604464 : if (riinfo->pk_is_partitioned)
3293 639 : return false;
3294 :
3295 : /*
3296 : * Temporal foreign keys use range overlap and containment semantics (&&,
3297 : * <@, range_agg()) that inherently involve aggregation and multiple-row
3298 : * reasoning, so they stay on the SPI path.
3299 : */
3300 603825 : if (riinfo->hasperiod)
3301 151 : return false;
3302 :
3303 603674 : return true;
3304 : }
3305 :
3306 : /*
3307 : * ri_CheckPermissions
3308 : * Check that the current user has permissions to look into the schema of
3309 : * and SELECT from 'query_rel'
3310 : */
3311 : static void
3312 11135 : ri_CheckPermissions(Relation query_rel)
3313 : {
3314 : AclResult aclresult;
3315 :
3316 : /* USAGE on schema. */
3317 11135 : aclresult = object_aclcheck(NamespaceRelationId,
3318 11135 : RelationGetNamespace(query_rel),
3319 : GetUserId(), ACL_USAGE);
3320 11135 : if (aclresult != ACLCHECK_OK)
3321 0 : aclcheck_error(aclresult, OBJECT_SCHEMA,
3322 0 : get_namespace_name(RelationGetNamespace(query_rel)));
3323 :
3324 : /* SELECT on relation. */
3325 11135 : aclresult = pg_class_aclcheck(RelationGetRelid(query_rel), GetUserId(),
3326 : ACL_SELECT);
3327 11135 : if (aclresult != ACLCHECK_OK)
3328 4 : aclcheck_error(aclresult, OBJECT_TABLE,
3329 4 : RelationGetRelationName(query_rel));
3330 11131 : }
3331 :
3332 : /*
3333 : * recheck_matched_pk_tuple
3334 : * After following an update chain (tmfd.traversed), verify that
3335 : * the locked PK tuple still matches the original search keys.
3336 : *
3337 : * A non-key update (e.g. changing a non-PK column) creates a new tuple version
3338 : * that we've now locked, but the key is unchanged -- that's fine. A key
3339 : * update means the value we were looking for is gone, so we should treat it as
3340 : * not found.
3341 : */
3342 : static bool
3343 2 : recheck_matched_pk_tuple(Relation idxrel, ScanKeyData *skeys,
3344 : TupleTableSlot *new_slot)
3345 : {
3346 : /*
3347 : * TODO: BuildIndexInfo does a syscache lookup + palloc on every call.
3348 : * This only fires on the concurrent-update path (tmfd.traversed), which
3349 : * should be rare, so the cost is acceptable for now. If profiling shows
3350 : * otherwise, cache the IndexInfo in FastPathMeta.
3351 : */
3352 2 : IndexInfo *indexInfo = BuildIndexInfo(idxrel);
3353 : Datum values[INDEX_MAX_KEYS];
3354 : bool isnull[INDEX_MAX_KEYS];
3355 2 : bool matched = true;
3356 :
3357 : /* PK indexes never have these. */
3358 : Assert(indexInfo->ii_Expressions == NIL &&
3359 : indexInfo->ii_ExclusionOps == NULL);
3360 :
3361 : /* Form the index values and isnull flags given the table tuple. */
3362 2 : FormIndexDatum(indexInfo, new_slot, NULL, values, isnull);
3363 3 : for (int i = 0; i < indexInfo->ii_NumIndexKeyAttrs; i++)
3364 : {
3365 2 : ScanKeyData *skey = &skeys[i];
3366 :
3367 : /* A PK column can never be set to NULL. */
3368 : Assert(!isnull[i]);
3369 2 : if (!DatumGetBool(FunctionCall2Coll(&skey->sk_func,
3370 : skey->sk_collation,
3371 : values[i],
3372 : skey->sk_argument)))
3373 : {
3374 1 : matched = false;
3375 1 : break;
3376 : }
3377 : }
3378 :
3379 2 : return matched;
3380 : }
3381 :
3382 : /*
3383 : * build_index_scankeys
3384 : * Build ScanKeys for a direct index probe of the PK's unique index.
3385 : *
3386 : * Uses cached compare entries, operator procedures, and strategy numbers
3387 : * from ri_populate_fastpath_metadata() rather than looking them up on
3388 : * each invocation. Casts FK values to the operator's expected input
3389 : * type if needed.
3390 : */
3391 : static void
3392 1990 : build_index_scankeys(const RI_ConstraintInfo *riinfo,
3393 : Relation idx_rel, Datum *pk_vals,
3394 : char *pk_nulls, ScanKey skeys)
3395 : {
3396 1990 : FastPathMeta *fpmeta = riinfo->fpmeta;
3397 :
3398 : Assert(fpmeta);
3399 :
3400 : /*
3401 : * May need to cast each of the individual values of the foreign key to
3402 : * the corresponding PK column's type if the equality operator demands it.
3403 : */
3404 4834 : for (int i = 0; i < riinfo->nkeys; i++)
3405 : {
3406 2844 : if (pk_nulls[i] != 'n' &&
3407 2844 : OidIsValid(fpmeta->cast_func_finfo[i].fn_oid))
3408 20 : pk_vals[i] = FunctionCall3(&fpmeta->cast_func_finfo[i],
3409 : pk_vals[i],
3410 : Int32GetDatum(-1), /* typmod */
3411 : BoolGetDatum(false)); /* implicit coercion */
3412 : }
3413 :
3414 : /*
3415 : * Set up ScanKeys for the index scan. This is essentially how
3416 : * ExecIndexBuildScanKeys() sets them up.
3417 : */
3418 4834 : for (int i = 0; i < riinfo->nkeys; i++)
3419 : {
3420 2844 : int pkattrno = i + 1;
3421 :
3422 2844 : ScanKeyEntryInitialize(&skeys[i], 0, pkattrno,
3423 2844 : fpmeta->strats[i], fpmeta->subtypes[i],
3424 2844 : idx_rel->rd_indcollation[i], fpmeta->regops[i],
3425 2844 : pk_vals[i]);
3426 : }
3427 1990 : }
3428 :
3429 : /*
3430 : * ri_populate_fastpath_metadata
3431 : * Cache per-key metadata needed by build_index_scankeys().
3432 : *
3433 : * Looks up the compare hash entry, operator procedure OID, and index
3434 : * strategy/subtype for each key column. Called lazily on first use
3435 : * and persists for the lifetime of the RI_ConstraintInfo entry.
3436 : */
3437 : static void
3438 943 : ri_populate_fastpath_metadata(RI_ConstraintInfo *riinfo,
3439 : Relation fk_rel, Relation idx_rel)
3440 : {
3441 : FastPathMeta *fpmeta;
3442 943 : MemoryContext oldcxt = MemoryContextSwitchTo(TopMemoryContext);
3443 :
3444 : Assert(riinfo != NULL && riinfo->valid);
3445 :
3446 943 : fpmeta = palloc_object(FastPathMeta);
3447 2022 : for (int i = 0; i < riinfo->nkeys; i++)
3448 : {
3449 1079 : Oid eq_opr = riinfo->pf_eq_oprs[i];
3450 1079 : Oid typeid = RIAttType(fk_rel, riinfo->fk_attnums[i]);
3451 : Oid lefttype;
3452 1079 : RI_CompareHashEntry *entry = ri_HashCompareOp(eq_opr, typeid);
3453 :
3454 1079 : fmgr_info_copy(&fpmeta->cast_func_finfo[i], &entry->cast_func_finfo,
3455 : CurrentMemoryContext);
3456 1079 : fmgr_info_copy(&fpmeta->eq_opr_finfo[i], &entry->eq_opr_finfo,
3457 : CurrentMemoryContext);
3458 1079 : fpmeta->regops[i] = get_opcode(eq_opr);
3459 :
3460 1079 : get_op_opfamily_properties(eq_opr,
3461 1079 : idx_rel->rd_opfamily[i],
3462 : false,
3463 : &fpmeta->strats[i],
3464 : &lefttype,
3465 : &fpmeta->subtypes[i]);
3466 : }
3467 :
3468 943 : riinfo->fpmeta = fpmeta;
3469 943 : MemoryContextSwitchTo(oldcxt);
3470 943 : }
3471 :
3472 : /*
3473 : * Extract fields from a tuple into Datum/nulls arrays
3474 : */
3475 : static void
3476 606276 : ri_ExtractValues(Relation rel, TupleTableSlot *slot,
3477 : const RI_ConstraintInfo *riinfo, bool rel_is_pk,
3478 : Datum *vals, char *nulls)
3479 : {
3480 : const int16 *attnums;
3481 : bool isnull;
3482 :
3483 606276 : if (rel_is_pk)
3484 1827 : attnums = riinfo->pk_attnums;
3485 : else
3486 604449 : attnums = riinfo->fk_attnums;
3487 :
3488 1214539 : for (int i = 0; i < riinfo->nkeys; i++)
3489 : {
3490 608263 : vals[i] = slot_getattr(slot, attnums[i], &isnull);
3491 608263 : nulls[i] = isnull ? 'n' : ' ';
3492 : }
3493 606276 : }
3494 :
3495 : /*
3496 : * Produce an error report
3497 : *
3498 : * If the failed constraint was on insert/update to the FK table,
3499 : * we want the key names and values extracted from there, and the error
3500 : * message to look like 'key blah is not present in PK'.
3501 : * Otherwise, the attr names and values come from the PK table and the
3502 : * message looks like 'key blah is still referenced from FK'.
3503 : */
3504 : static void
3505 813 : ri_ReportViolation(const RI_ConstraintInfo *riinfo,
3506 : Relation pk_rel, Relation fk_rel,
3507 : TupleTableSlot *violatorslot, TupleDesc tupdesc,
3508 : int queryno, bool is_restrict, bool partgone)
3509 : {
3510 : StringInfoData key_names;
3511 : StringInfoData key_values;
3512 : bool onfk;
3513 : const int16 *attnums;
3514 : Oid rel_oid;
3515 : AclResult aclresult;
3516 813 : bool has_perm = true;
3517 :
3518 : /*
3519 : * Determine which relation to complain about. If tupdesc wasn't passed
3520 : * by caller, assume the violator tuple came from there.
3521 : */
3522 813 : onfk = (queryno == RI_PLAN_CHECK_LOOKUPPK);
3523 813 : if (onfk)
3524 : {
3525 461 : attnums = riinfo->fk_attnums;
3526 461 : rel_oid = fk_rel->rd_id;
3527 461 : if (tupdesc == NULL)
3528 410 : tupdesc = fk_rel->rd_att;
3529 : }
3530 : else
3531 : {
3532 352 : attnums = riinfo->pk_attnums;
3533 352 : rel_oid = pk_rel->rd_id;
3534 352 : if (tupdesc == NULL)
3535 330 : tupdesc = pk_rel->rd_att;
3536 : }
3537 :
3538 : /*
3539 : * Check permissions- if the user does not have access to view the data in
3540 : * any of the key columns then we don't include the errdetail() below.
3541 : *
3542 : * Check if RLS is enabled on the relation first. If so, we don't return
3543 : * any specifics to avoid leaking data.
3544 : *
3545 : * Check table-level permissions next and, failing that, column-level
3546 : * privileges.
3547 : *
3548 : * When a partition at the referenced side is being detached/dropped, we
3549 : * needn't check, since the user must be the table owner anyway.
3550 : */
3551 813 : if (partgone)
3552 22 : has_perm = true;
3553 791 : else if (check_enable_rls(rel_oid, InvalidOid, true) != RLS_ENABLED)
3554 : {
3555 787 : aclresult = pg_class_aclcheck(rel_oid, GetUserId(), ACL_SELECT);
3556 787 : if (aclresult != ACLCHECK_OK)
3557 : {
3558 : /* Try for column-level permissions */
3559 0 : for (int idx = 0; idx < riinfo->nkeys; idx++)
3560 : {
3561 0 : aclresult = pg_attribute_aclcheck(rel_oid, attnums[idx],
3562 : GetUserId(),
3563 : ACL_SELECT);
3564 :
3565 : /* No access to the key */
3566 0 : if (aclresult != ACLCHECK_OK)
3567 : {
3568 0 : has_perm = false;
3569 0 : break;
3570 : }
3571 : }
3572 : }
3573 : }
3574 : else
3575 4 : has_perm = false;
3576 :
3577 813 : if (has_perm)
3578 : {
3579 : /* Get printable versions of the keys involved */
3580 809 : initStringInfo(&key_names);
3581 809 : initStringInfo(&key_values);
3582 1993 : for (int idx = 0; idx < riinfo->nkeys; idx++)
3583 : {
3584 1184 : int fnum = attnums[idx];
3585 1184 : Form_pg_attribute att = TupleDescAttr(tupdesc, fnum - 1);
3586 : char *name,
3587 : *val;
3588 : Datum datum;
3589 : bool isnull;
3590 :
3591 1184 : name = NameStr(att->attname);
3592 :
3593 1184 : datum = slot_getattr(violatorslot, fnum, &isnull);
3594 1184 : if (!isnull)
3595 : {
3596 : Oid foutoid;
3597 : bool typisvarlena;
3598 :
3599 1184 : getTypeOutputInfo(att->atttypid, &foutoid, &typisvarlena);
3600 1184 : val = OidOutputFunctionCall(foutoid, datum);
3601 : }
3602 : else
3603 0 : val = "null";
3604 :
3605 1184 : if (idx > 0)
3606 : {
3607 375 : appendStringInfoString(&key_names, ", ");
3608 375 : appendStringInfoString(&key_values, ", ");
3609 : }
3610 1184 : appendStringInfoString(&key_names, name);
3611 1184 : appendStringInfoString(&key_values, val);
3612 : }
3613 : }
3614 :
3615 813 : if (partgone)
3616 22 : ereport(ERROR,
3617 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
3618 : errmsg("removing partition \"%s\" violates foreign key constraint \"%s\"",
3619 : RelationGetRelationName(pk_rel),
3620 : NameStr(riinfo->conname)),
3621 : errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
3622 : key_names.data, key_values.data,
3623 : RelationGetRelationName(fk_rel)),
3624 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
3625 791 : else if (onfk)
3626 461 : ereport(ERROR,
3627 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
3628 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
3629 : RelationGetRelationName(fk_rel),
3630 : NameStr(riinfo->conname)),
3631 : has_perm ?
3632 : errdetail("Key (%s)=(%s) is not present in table \"%s\".",
3633 : key_names.data, key_values.data,
3634 : RelationGetRelationName(pk_rel)) :
3635 : errdetail("Key is not present in table \"%s\".",
3636 : RelationGetRelationName(pk_rel)),
3637 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
3638 330 : else if (is_restrict)
3639 20 : ereport(ERROR,
3640 : (errcode(ERRCODE_RESTRICT_VIOLATION),
3641 : errmsg("update or delete on table \"%s\" violates RESTRICT setting of foreign key constraint \"%s\" on table \"%s\"",
3642 : RelationGetRelationName(pk_rel),
3643 : NameStr(riinfo->conname),
3644 : RelationGetRelationName(fk_rel)),
3645 : has_perm ?
3646 : errdetail("Key (%s)=(%s) is referenced from table \"%s\".",
3647 : key_names.data, key_values.data,
3648 : RelationGetRelationName(fk_rel)) :
3649 : errdetail("Key is referenced from table \"%s\".",
3650 : RelationGetRelationName(fk_rel)),
3651 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
3652 : else
3653 310 : ereport(ERROR,
3654 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
3655 : errmsg("update or delete on table \"%s\" violates foreign key constraint \"%s\" on table \"%s\"",
3656 : RelationGetRelationName(pk_rel),
3657 : NameStr(riinfo->conname),
3658 : RelationGetRelationName(fk_rel)),
3659 : has_perm ?
3660 : errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
3661 : key_names.data, key_values.data,
3662 : RelationGetRelationName(fk_rel)) :
3663 : errdetail("Key is still referenced from table \"%s\".",
3664 : RelationGetRelationName(fk_rel)),
3665 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
3666 : }
3667 :
3668 :
3669 : /*
3670 : * ri_NullCheck -
3671 : *
3672 : * Determine the NULL state of all key values in a tuple
3673 : *
3674 : * Returns one of RI_KEYS_ALL_NULL, RI_KEYS_NONE_NULL or RI_KEYS_SOME_NULL.
3675 : */
3676 : static int
3677 606886 : ri_NullCheck(TupleDesc tupDesc,
3678 : TupleTableSlot *slot,
3679 : const RI_ConstraintInfo *riinfo, bool rel_is_pk)
3680 : {
3681 : const int16 *attnums;
3682 606886 : bool allnull = true;
3683 606886 : bool nonenull = true;
3684 :
3685 606886 : if (rel_is_pk)
3686 1532 : attnums = riinfo->pk_attnums;
3687 : else
3688 605354 : attnums = riinfo->fk_attnums;
3689 :
3690 1215861 : for (int i = 0; i < riinfo->nkeys; i++)
3691 : {
3692 608975 : if (slot_attisnull(slot, attnums[i]))
3693 366 : nonenull = false;
3694 : else
3695 608609 : allnull = false;
3696 : }
3697 :
3698 606886 : if (allnull)
3699 182 : return RI_KEYS_ALL_NULL;
3700 :
3701 606704 : if (nonenull)
3702 606568 : return RI_KEYS_NONE_NULL;
3703 :
3704 136 : return RI_KEYS_SOME_NULL;
3705 : }
3706 :
3707 :
3708 : /*
3709 : * ri_InitHashTables -
3710 : *
3711 : * Initialize our internal hash tables.
3712 : */
3713 : static void
3714 264 : ri_InitHashTables(void)
3715 : {
3716 : HASHCTL ctl;
3717 :
3718 264 : ctl.keysize = sizeof(Oid);
3719 264 : ctl.entrysize = sizeof(RI_ConstraintInfo);
3720 264 : ri_constraint_cache = hash_create("RI constraint cache",
3721 : RI_INIT_CONSTRAINTHASHSIZE,
3722 : &ctl, HASH_ELEM | HASH_BLOBS);
3723 :
3724 : /* Arrange to flush cache on pg_constraint changes */
3725 264 : CacheRegisterSyscacheCallback(CONSTROID,
3726 : InvalidateConstraintCacheCallBack,
3727 : (Datum) 0);
3728 :
3729 264 : ctl.keysize = sizeof(RI_QueryKey);
3730 264 : ctl.entrysize = sizeof(RI_QueryHashEntry);
3731 264 : ri_query_cache = hash_create("RI query cache",
3732 : RI_INIT_QUERYHASHSIZE,
3733 : &ctl, HASH_ELEM | HASH_BLOBS);
3734 :
3735 264 : ctl.keysize = sizeof(RI_CompareKey);
3736 264 : ctl.entrysize = sizeof(RI_CompareHashEntry);
3737 264 : ri_compare_cache = hash_create("RI compare cache",
3738 : RI_INIT_QUERYHASHSIZE,
3739 : &ctl, HASH_ELEM | HASH_BLOBS);
3740 264 : }
3741 :
3742 :
3743 : /*
3744 : * ri_FetchPreparedPlan -
3745 : *
3746 : * Lookup for a query key in our private hash table of prepared
3747 : * and saved SPI execution plans. Return the plan if found or NULL.
3748 : */
3749 : static SPIPlanPtr
3750 2473 : ri_FetchPreparedPlan(RI_QueryKey *key)
3751 : {
3752 : RI_QueryHashEntry *entry;
3753 : SPIPlanPtr plan;
3754 :
3755 : /*
3756 : * On the first call initialize the hashtable
3757 : */
3758 2473 : if (!ri_query_cache)
3759 0 : ri_InitHashTables();
3760 :
3761 : /*
3762 : * Lookup for the key
3763 : */
3764 2473 : entry = (RI_QueryHashEntry *) hash_search(ri_query_cache,
3765 : key,
3766 : HASH_FIND, NULL);
3767 2473 : if (entry == NULL)
3768 1018 : return NULL;
3769 :
3770 : /*
3771 : * Check whether the plan is still valid. If it isn't, we don't want to
3772 : * simply rely on plancache.c to regenerate it; rather we should start
3773 : * from scratch and rebuild the query text too. This is to cover cases
3774 : * such as table/column renames. We depend on the plancache machinery to
3775 : * detect possible invalidations, though.
3776 : *
3777 : * CAUTION: this check is only trustworthy if the caller has already
3778 : * locked both FK and PK rels.
3779 : */
3780 1455 : plan = entry->plan;
3781 1455 : if (plan && SPI_plan_is_valid(plan))
3782 1307 : return plan;
3783 :
3784 : /*
3785 : * Otherwise we might as well flush the cached plan now, to free a little
3786 : * memory space before we make a new one.
3787 : */
3788 148 : entry->plan = NULL;
3789 148 : if (plan)
3790 148 : SPI_freeplan(plan);
3791 :
3792 148 : return NULL;
3793 : }
3794 :
3795 :
3796 : /*
3797 : * ri_HashPreparedPlan -
3798 : *
3799 : * Add another plan to our private SPI query plan hashtable.
3800 : */
3801 : static void
3802 1166 : ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan)
3803 : {
3804 : RI_QueryHashEntry *entry;
3805 : bool found;
3806 :
3807 : /*
3808 : * On the first call initialize the hashtable
3809 : */
3810 1166 : if (!ri_query_cache)
3811 0 : ri_InitHashTables();
3812 :
3813 : /*
3814 : * Add the new plan. We might be overwriting an entry previously found
3815 : * invalid by ri_FetchPreparedPlan.
3816 : */
3817 1166 : entry = (RI_QueryHashEntry *) hash_search(ri_query_cache,
3818 : key,
3819 : HASH_ENTER, &found);
3820 : Assert(!found || entry->plan == NULL);
3821 1166 : entry->plan = plan;
3822 1166 : }
3823 :
3824 :
3825 : /*
3826 : * ri_KeysEqual -
3827 : *
3828 : * Check if all key values in OLD and NEW are "equivalent":
3829 : * For normal FKs we check for equality.
3830 : * For temporal FKs we check that the PK side is a superset of its old value,
3831 : * or the FK side is a subset of its old value.
3832 : *
3833 : * Note: at some point we might wish to redefine this as checking for
3834 : * "IS NOT DISTINCT" rather than "=", that is, allow two nulls to be
3835 : * considered equal. Currently there is no need since all callers have
3836 : * previously found at least one of the rows to contain no nulls.
3837 : */
3838 : static bool
3839 1423 : ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot,
3840 : const RI_ConstraintInfo *riinfo, bool rel_is_pk)
3841 : {
3842 : const int16 *attnums;
3843 :
3844 1423 : if (rel_is_pk)
3845 936 : attnums = riinfo->pk_attnums;
3846 : else
3847 487 : attnums = riinfo->fk_attnums;
3848 :
3849 : /* XXX: could be worthwhile to fetch all necessary attrs at once */
3850 2193 : for (int i = 0; i < riinfo->nkeys; i++)
3851 : {
3852 : Datum oldvalue;
3853 : Datum newvalue;
3854 : bool isnull;
3855 :
3856 : /*
3857 : * Get one attribute's oldvalue. If it is NULL - they're not equal.
3858 : */
3859 1643 : oldvalue = slot_getattr(oldslot, attnums[i], &isnull);
3860 1643 : if (isnull)
3861 873 : return false;
3862 :
3863 : /*
3864 : * Get one attribute's newvalue. If it is NULL - they're not equal.
3865 : */
3866 1625 : newvalue = slot_getattr(newslot, attnums[i], &isnull);
3867 1625 : if (isnull)
3868 0 : return false;
3869 :
3870 1625 : if (rel_is_pk)
3871 : {
3872 : /*
3873 : * If we are looking at the PK table, then do a bytewise
3874 : * comparison. We must propagate PK changes if the value is
3875 : * changed to one that "looks" different but would compare as
3876 : * equal using the equality operator. This only makes a
3877 : * difference for ON UPDATE CASCADE, but for consistency we treat
3878 : * all changes to the PK the same.
3879 : */
3880 1100 : CompactAttribute *att = TupleDescCompactAttr(oldslot->tts_tupleDescriptor, attnums[i] - 1);
3881 :
3882 1100 : if (!datum_image_eq(oldvalue, newvalue, att->attbyval, att->attlen))
3883 648 : return false;
3884 : }
3885 : else
3886 : {
3887 : Oid eq_opr;
3888 :
3889 : /*
3890 : * When comparing the PERIOD columns we can skip the check
3891 : * whenever the referencing column stayed equal or shrank, so test
3892 : * with the contained-by operator instead.
3893 : */
3894 525 : if (riinfo->hasperiod && i == riinfo->nkeys - 1)
3895 32 : eq_opr = riinfo->period_contained_by_oper;
3896 : else
3897 493 : eq_opr = riinfo->ff_eq_oprs[i];
3898 :
3899 : /*
3900 : * For the FK table, compare with the appropriate equality
3901 : * operator. Changes that compare equal will still satisfy the
3902 : * constraint after the update.
3903 : */
3904 525 : if (!ri_CompareWithCast(eq_opr, RIAttType(rel, attnums[i]), RIAttCollation(rel, attnums[i]),
3905 : newvalue, oldvalue))
3906 207 : return false;
3907 : }
3908 : }
3909 :
3910 550 : return true;
3911 : }
3912 :
3913 :
3914 : /*
3915 : * ri_CompareWithCast -
3916 : *
3917 : * Call the appropriate comparison operator for two values.
3918 : * Normally this is equality, but for the PERIOD part of foreign keys
3919 : * it is ContainedBy, so the order of lhs vs rhs is significant.
3920 : * See below for how the collation is applied.
3921 : *
3922 : * NB: we have already checked that neither value is null.
3923 : */
3924 : static bool
3925 525 : ri_CompareWithCast(Oid eq_opr, Oid typeid, Oid collid,
3926 : Datum lhs, Datum rhs)
3927 : {
3928 525 : RI_CompareHashEntry *entry = ri_HashCompareOp(eq_opr, typeid);
3929 :
3930 : /* Do we need to cast the values? */
3931 525 : if (OidIsValid(entry->cast_func_finfo.fn_oid))
3932 : {
3933 8 : lhs = FunctionCall3(&entry->cast_func_finfo,
3934 : lhs,
3935 : Int32GetDatum(-1), /* typmod */
3936 : BoolGetDatum(false)); /* implicit coercion */
3937 8 : rhs = FunctionCall3(&entry->cast_func_finfo,
3938 : rhs,
3939 : Int32GetDatum(-1), /* typmod */
3940 : BoolGetDatum(false)); /* implicit coercion */
3941 : }
3942 :
3943 : /*
3944 : * Apply the comparison operator.
3945 : *
3946 : * Note: This function is part of a call stack that determines whether an
3947 : * update to a row is significant enough that it needs checking or action
3948 : * on the other side of a foreign-key constraint. Therefore, the
3949 : * comparison here would need to be done with the collation of the *other*
3950 : * table. For simplicity (e.g., we might not even have the other table
3951 : * open), we'll use our own collation. This is fine because we require
3952 : * that both collations have the same notion of equality (either they are
3953 : * both deterministic or else they are both the same).
3954 : *
3955 : * With range/multirangetypes, the collation of the base type is stored as
3956 : * part of the rangetype (pg_range.rngcollation), and always used, so
3957 : * there is no danger of inconsistency even using a non-equals operator.
3958 : * But if we support arbitrary types with PERIOD, we should perhaps just
3959 : * always force a re-check.
3960 : */
3961 525 : return DatumGetBool(FunctionCall2Coll(&entry->eq_opr_finfo, collid, lhs, rhs));
3962 : }
3963 :
3964 : /*
3965 : * ri_HashCompareOp -
3966 : *
3967 : * Look up or create a cache entry for the given equality operator and
3968 : * the caller's value type (typeid). The entry holds the operator's
3969 : * FmgrInfo and, if typeid doesn't match what the operator expects as
3970 : * its right-hand input, a cast function to coerce the value before
3971 : * comparison.
3972 : */
3973 : static RI_CompareHashEntry *
3974 1604 : ri_HashCompareOp(Oid eq_opr, Oid typeid)
3975 : {
3976 : RI_CompareKey key;
3977 : RI_CompareHashEntry *entry;
3978 : bool found;
3979 :
3980 : /*
3981 : * On the first call initialize the hashtable
3982 : */
3983 1604 : if (!ri_compare_cache)
3984 0 : ri_InitHashTables();
3985 :
3986 : /*
3987 : * Find or create a hash entry. Note we're assuming RI_CompareKey
3988 : * contains no struct padding.
3989 : */
3990 1604 : key.eq_opr = eq_opr;
3991 1604 : key.typeid = typeid;
3992 1604 : entry = (RI_CompareHashEntry *) hash_search(ri_compare_cache,
3993 : &key,
3994 : HASH_ENTER, &found);
3995 1604 : if (!found)
3996 252 : entry->valid = false;
3997 :
3998 : /*
3999 : * If not already initialized, do so. Since we'll keep this hash entry
4000 : * for the life of the backend, put any subsidiary info for the function
4001 : * cache structs into TopMemoryContext.
4002 : */
4003 1604 : if (!entry->valid)
4004 : {
4005 : Oid lefttype,
4006 : righttype,
4007 : castfunc;
4008 : CoercionPathType pathtype;
4009 :
4010 : /* We always need to know how to call the equality operator */
4011 252 : fmgr_info_cxt(get_opcode(eq_opr), &entry->eq_opr_finfo,
4012 : TopMemoryContext);
4013 :
4014 : /*
4015 : * If we chose to use a cast from FK to PK type, we may have to apply
4016 : * the cast function to get to the operator's input type.
4017 : *
4018 : * XXX eventually it would be good to support array-coercion cases
4019 : * here and in ri_CompareWithCast(). At the moment there is no point
4020 : * because cases involving nonidentical array types will be rejected
4021 : * at constraint creation time.
4022 : *
4023 : * XXX perhaps also consider supporting CoerceViaIO? No need at the
4024 : * moment since that will never be generated for implicit coercions.
4025 : */
4026 252 : op_input_types(eq_opr, &lefttype, &righttype);
4027 :
4028 : /*
4029 : * pf_eq_oprs (used by the fast path) can be cross-type when the FK
4030 : * and PK columns differ in type, e.g. int48eq for int4 PK / int8 FK.
4031 : * If the FK column's type already matches what the operator expects
4032 : * as its right-hand input, no cast is needed.
4033 : */
4034 252 : if (typeid == righttype)
4035 228 : castfunc = InvalidOid; /* simplest case */
4036 : else
4037 : {
4038 24 : pathtype = find_coercion_pathway(lefttype, typeid,
4039 : COERCION_IMPLICIT,
4040 : &castfunc);
4041 24 : if (pathtype != COERCION_PATH_FUNC &&
4042 : pathtype != COERCION_PATH_RELABELTYPE)
4043 : {
4044 : /*
4045 : * The declared input type of the eq_opr might be a
4046 : * polymorphic type such as ANYARRAY or ANYENUM, or other
4047 : * special cases such as RECORD; find_coercion_pathway
4048 : * currently doesn't subsume these special cases.
4049 : */
4050 16 : if (!IsBinaryCoercible(typeid, lefttype))
4051 0 : elog(ERROR, "no conversion function from %s to %s",
4052 : format_type_be(typeid),
4053 : format_type_be(lefttype));
4054 : }
4055 : }
4056 252 : if (OidIsValid(castfunc))
4057 8 : fmgr_info_cxt(castfunc, &entry->cast_func_finfo,
4058 : TopMemoryContext);
4059 : else
4060 244 : entry->cast_func_finfo.fn_oid = InvalidOid;
4061 252 : entry->valid = true;
4062 : }
4063 :
4064 1604 : return entry;
4065 : }
4066 :
4067 :
4068 : /*
4069 : * Given a trigger function OID, determine whether it is an RI trigger,
4070 : * and if so whether it is attached to PK or FK relation.
4071 : */
4072 : int
4073 5787 : RI_FKey_trigger_type(Oid tgfoid)
4074 : {
4075 5787 : switch (tgfoid)
4076 : {
4077 2032 : case F_RI_FKEY_CASCADE_DEL:
4078 : case F_RI_FKEY_CASCADE_UPD:
4079 : case F_RI_FKEY_RESTRICT_DEL:
4080 : case F_RI_FKEY_RESTRICT_UPD:
4081 : case F_RI_FKEY_SETNULL_DEL:
4082 : case F_RI_FKEY_SETNULL_UPD:
4083 : case F_RI_FKEY_SETDEFAULT_DEL:
4084 : case F_RI_FKEY_SETDEFAULT_UPD:
4085 : case F_RI_FKEY_NOACTION_DEL:
4086 : case F_RI_FKEY_NOACTION_UPD:
4087 2032 : return RI_TRIGGER_PK;
4088 :
4089 1850 : case F_RI_FKEY_CHECK_INS:
4090 : case F_RI_FKEY_CHECK_UPD:
4091 1850 : return RI_TRIGGER_FK;
4092 : }
4093 :
4094 1905 : return RI_TRIGGER_NONE;
4095 : }
4096 :
4097 : /*
4098 : * ri_FastPathEndBatch
4099 : * Flush remaining rows and tear down cached state.
4100 : *
4101 : * Registered as an AfterTriggerBatchCallback. Note: the flush can
4102 : * do real work (CCI, security context switch, index probes) and can
4103 : * throw ERROR on a constraint violation. If that happens,
4104 : * ri_FastPathTeardown never runs; ResourceOwner + XactCallback
4105 : * handle resource cleanup on the abort path.
4106 : */
4107 : static void
4108 1477 : ri_FastPathEndBatch(void *arg)
4109 : {
4110 : HASH_SEQ_STATUS status;
4111 : RI_FastPathEntry *entry;
4112 :
4113 1477 : if (ri_fastpath_cache == NULL)
4114 1 : return;
4115 :
4116 : /* Flush any partial batches -- can throw ERROR */
4117 1476 : hash_seq_init(&status, ri_fastpath_cache);
4118 4367 : while ((entry = hash_seq_search(&status)) != NULL)
4119 : {
4120 1699 : if (entry->batch_count > 0)
4121 : {
4122 1699 : Relation fk_rel = table_open(entry->fk_relid, AccessShareLock);
4123 1699 : const RI_ConstraintInfo *riinfo = ri_LoadConstraintInfo(entry->conoid);
4124 :
4125 1699 : ri_FastPathBatchFlush(entry, fk_rel, riinfo);
4126 1415 : table_close(fk_rel, NoLock);
4127 : }
4128 : }
4129 :
4130 1192 : ri_FastPathTeardown();
4131 : }
4132 :
4133 : /*
4134 : * ri_FastPathTeardown
4135 : * Tear down all cached fast-path state.
4136 : *
4137 : * Called from ri_FastPathEndBatch() after flushing any remaining rows.
4138 : */
4139 : static void
4140 1192 : ri_FastPathTeardown(void)
4141 : {
4142 : HASH_SEQ_STATUS status;
4143 : RI_FastPathEntry *entry;
4144 :
4145 1192 : if (ri_fastpath_cache == NULL)
4146 0 : return;
4147 :
4148 1192 : hash_seq_init(&status, ri_fastpath_cache);
4149 3782 : while ((entry = hash_seq_search(&status)) != NULL)
4150 : {
4151 1398 : if (entry->idx_rel)
4152 1398 : index_close(entry->idx_rel, NoLock);
4153 1398 : if (entry->pk_rel)
4154 1398 : table_close(entry->pk_rel, NoLock);
4155 1398 : if (entry->pk_slot)
4156 1398 : ExecDropSingleTupleTableSlot(entry->pk_slot);
4157 1398 : if (entry->fk_slot)
4158 1398 : ExecDropSingleTupleTableSlot(entry->fk_slot);
4159 1398 : if (entry->flush_cxt)
4160 1398 : MemoryContextDelete(entry->flush_cxt);
4161 : }
4162 :
4163 1192 : hash_destroy(ri_fastpath_cache);
4164 1192 : ri_fastpath_cache = NULL;
4165 1192 : ri_fastpath_callback_registered = false;
4166 : }
4167 :
4168 : static bool ri_fastpath_xact_callback_registered = false;
4169 :
4170 : static void
4171 73026 : ri_FastPathXactCallback(XactEvent event, void *arg)
4172 : {
4173 : /*
4174 : * On abort, ResourceOwner already released relations; on commit,
4175 : * ri_FastPathTeardown already ran. Either way, just NULL the static
4176 : * pointers so they don't dangle into the next transaction.
4177 : */
4178 73026 : ri_fastpath_cache = NULL;
4179 73026 : ri_fastpath_callback_registered = false;
4180 73026 : }
4181 :
4182 : static void
4183 333 : ri_FastPathSubXactCallback(SubXactEvent event, SubTransactionId mySubid,
4184 : SubTransactionId parentSubid, void *arg)
4185 : {
4186 333 : if (event == SUBXACT_EVENT_ABORT_SUB)
4187 : {
4188 : /*
4189 : * ResourceOwner already released relations. NULL the static pointers
4190 : * so the still-registered batch callback becomes a no-op for the rest
4191 : * of this transaction.
4192 : */
4193 90 : ri_fastpath_cache = NULL;
4194 90 : ri_fastpath_callback_registered = false;
4195 : }
4196 333 : }
4197 :
4198 : /*
4199 : * ri_FastPathGetEntry
4200 : * Look up or create a per-batch cache entry for the given constraint.
4201 : *
4202 : * On first call for a constraint within a batch: opens pk_rel and the index,
4203 : * allocates slots for both FK row and the looked up PK row, and registers the
4204 : * cleanup callback.
4205 : *
4206 : * On subsequent calls: returns the existing entry.
4207 : */
4208 : static RI_FastPathEntry *
4209 603630 : ri_FastPathGetEntry(const RI_ConstraintInfo *riinfo, Relation fk_rel)
4210 : {
4211 : RI_FastPathEntry *entry;
4212 : bool found;
4213 :
4214 : /* Create hash table on first use in this batch */
4215 603630 : if (ri_fastpath_cache == NULL)
4216 : {
4217 : HASHCTL ctl;
4218 :
4219 1476 : if (!ri_fastpath_xact_callback_registered)
4220 : {
4221 213 : RegisterXactCallback(ri_FastPathXactCallback, NULL);
4222 213 : RegisterSubXactCallback(ri_FastPathSubXactCallback, NULL);
4223 213 : ri_fastpath_xact_callback_registered = true;
4224 : }
4225 :
4226 1476 : ctl.keysize = sizeof(Oid);
4227 1476 : ctl.entrysize = sizeof(RI_FastPathEntry);
4228 1476 : ctl.hcxt = TopTransactionContext;
4229 1476 : ri_fastpath_cache = hash_create("RI fast-path cache",
4230 : 16,
4231 : &ctl,
4232 : HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
4233 : }
4234 :
4235 603630 : entry = hash_search(ri_fastpath_cache, &riinfo->constraint_id,
4236 : HASH_ENTER, &found);
4237 :
4238 603630 : if (!found)
4239 : {
4240 : MemoryContext oldcxt;
4241 :
4242 : /*
4243 : * Zero out non-key fields so ri_FastPathTeardown is safe if we error
4244 : * out during partial initialization below.
4245 : */
4246 1710 : memset(((char *) entry) + offsetof(RI_FastPathEntry, pk_rel), 0,
4247 : sizeof(RI_FastPathEntry) - offsetof(RI_FastPathEntry, pk_rel));
4248 :
4249 1710 : oldcxt = MemoryContextSwitchTo(TopTransactionContext);
4250 :
4251 1710 : entry->fk_relid = RelationGetRelid(fk_rel);
4252 :
4253 : /*
4254 : * Open PK table and its unique index.
4255 : *
4256 : * RowShareLock on pk_rel matches what the SPI path's SELECT ... FOR
4257 : * KEY SHARE would acquire as a relation-level lock. AccessShareLock
4258 : * on the index is standard for index scans.
4259 : *
4260 : * We don't release these locks until end of transaction, matching SPI
4261 : * behavior.
4262 : */
4263 1710 : entry->pk_rel = table_open(riinfo->pk_relid, RowShareLock);
4264 1710 : entry->idx_rel = index_open(riinfo->conindid, AccessShareLock);
4265 1710 : entry->pk_slot = table_slot_create(entry->pk_rel, NULL);
4266 :
4267 : /*
4268 : * Must be TTSOpsHeapTuple because ExecStoreHeapTuple() is used to
4269 : * load entries from batch[] into this slot for value extraction.
4270 : */
4271 1710 : entry->fk_slot = MakeSingleTupleTableSlot(RelationGetDescr(fk_rel),
4272 : &TTSOpsHeapTuple);
4273 :
4274 1710 : entry->flush_cxt = AllocSetContextCreate(TopTransactionContext,
4275 : "RI fast path flush temporary context",
4276 : ALLOCSET_SMALL_SIZES);
4277 1710 : MemoryContextSwitchTo(oldcxt);
4278 :
4279 : /* Ensure cleanup at end of this trigger-firing batch */
4280 1710 : if (!ri_fastpath_callback_registered)
4281 : {
4282 1476 : RegisterAfterTriggerBatchCallback(ri_FastPathEndBatch, NULL);
4283 1476 : ri_fastpath_callback_registered = true;
4284 : }
4285 : }
4286 :
4287 603630 : return entry;
4288 : }
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