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 : AttrNumber index_attnos[RI_MAX_NUMKEYS]; /* index column positions */
160 : } FastPathMeta;
161 :
162 : /*
163 : * RI_QueryKey
164 : *
165 : * The key identifying a prepared SPI plan in our query hashtable
166 : */
167 : typedef struct RI_QueryKey
168 : {
169 : Oid constr_id; /* OID of pg_constraint entry */
170 : int32 constr_queryno; /* query type ID, see RI_PLAN_XXX above */
171 : } RI_QueryKey;
172 :
173 : /*
174 : * RI_QueryHashEntry
175 : */
176 : typedef struct RI_QueryHashEntry
177 : {
178 : RI_QueryKey key;
179 : SPIPlanPtr plan;
180 : } RI_QueryHashEntry;
181 :
182 : /*
183 : * RI_CompareKey
184 : *
185 : * The key identifying an entry showing how to compare two values
186 : */
187 : typedef struct RI_CompareKey
188 : {
189 : Oid eq_opr; /* the equality operator to apply */
190 : Oid typeid; /* the data type to apply it to */
191 : } RI_CompareKey;
192 :
193 : /*
194 : * RI_CompareHashEntry
195 : */
196 : typedef struct RI_CompareHashEntry
197 : {
198 : RI_CompareKey key;
199 : bool valid; /* successfully initialized? */
200 : FmgrInfo eq_opr_finfo; /* call info for equality fn */
201 : FmgrInfo cast_func_finfo; /* in case we must coerce input */
202 : } RI_CompareHashEntry;
203 :
204 : /*
205 : * Maximum number of FK rows buffered before flushing.
206 : *
207 : * Larger batches amortize per-flush overhead and let the SK_SEARCHARRAY
208 : * path walk more leaf pages in a single sorted traversal. But each
209 : * buffered row is a materialized HeapTuple in flush_cxt, and the matched[]
210 : * scan in ri_FastPathFlushArray() is O(batch_size) per index match.
211 : * Benchmarking showed little difference between 16 and 64, with 256
212 : * consistently slower. 64 is a reasonable default.
213 : */
214 : #define RI_FASTPATH_BATCH_SIZE 64
215 :
216 : /*
217 : * RI_FastPathEntry
218 : * Per-constraint cache of resources needed by ri_FastPathBatchFlush().
219 : *
220 : * One entry per constraint, keyed by pg_constraint OID. Created lazily
221 : * by ri_FastPathGetEntry() on first use within a trigger-firing batch
222 : * and torn down by ri_FastPathTeardown() at batch end.
223 : *
224 : * FK tuples are buffered in batch[] across trigger invocations and
225 : * flushed when the buffer fills or the batch ends.
226 : *
227 : * RI_FastPathEntry is not subject to cache invalidation. The cached
228 : * relations are held open with locks for the transaction duration, preventing
229 : * relcache invalidation. The entry itself is torn down at batch end by
230 : * ri_FastPathEndBatch(); on abort, ResourceOwner releases the cached
231 : * relations and the XactCallback/SubXactCallback NULL the static cache pointer
232 : * to prevent any subsequent access.
233 : */
234 : typedef struct RI_FastPathEntry
235 : {
236 : Oid conoid; /* hash key: pg_constraint OID */
237 : Oid fk_relid; /* for ri_FastPathEndBatch() */
238 : Relation pk_rel;
239 : Relation idx_rel;
240 : TupleTableSlot *pk_slot;
241 : TupleTableSlot *fk_slot;
242 : MemoryContext flush_cxt; /* short-lived context for per-flush work */
243 :
244 : /*
245 : * TODO: batch[] is HeapTuple[] because the AFTER trigger machinery
246 : * currently passes tuples as HeapTuples. Once trigger infrastructure is
247 : * slotified, this should use a slot array or whatever batched tuple
248 : * storage abstraction exists at that point to be TAM-agnostic.
249 : */
250 : HeapTuple batch[RI_FASTPATH_BATCH_SIZE];
251 : int batch_count;
252 : } RI_FastPathEntry;
253 :
254 : /*
255 : * Local data
256 : */
257 : static HTAB *ri_constraint_cache = NULL;
258 : static HTAB *ri_query_cache = NULL;
259 : static HTAB *ri_compare_cache = NULL;
260 : static dclist_head ri_constraint_cache_valid_list;
261 :
262 : static HTAB *ri_fastpath_cache = NULL;
263 : static bool ri_fastpath_callback_registered = false;
264 :
265 : /*
266 : * Local function prototypes
267 : */
268 : static bool ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
269 : TupleTableSlot *oldslot,
270 : const RI_ConstraintInfo *riinfo);
271 : static Datum ri_restrict(TriggerData *trigdata, bool is_no_action);
272 : static Datum ri_set(TriggerData *trigdata, bool is_set_null, int tgkind);
273 : static void quoteOneName(char *buffer, const char *name);
274 : static void quoteRelationName(char *buffer, Relation rel);
275 : static void ri_GenerateQual(StringInfo buf,
276 : const char *sep,
277 : const char *leftop, Oid leftoptype,
278 : Oid opoid,
279 : const char *rightop, Oid rightoptype);
280 : static void ri_GenerateQualCollation(StringInfo buf, Oid collation);
281 : static int ri_NullCheck(TupleDesc tupDesc, TupleTableSlot *slot,
282 : const RI_ConstraintInfo *riinfo, bool rel_is_pk);
283 : static void ri_BuildQueryKey(RI_QueryKey *key,
284 : const RI_ConstraintInfo *riinfo,
285 : int32 constr_queryno);
286 : static bool ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot,
287 : const RI_ConstraintInfo *riinfo, bool rel_is_pk);
288 : static bool ri_CompareWithCast(Oid eq_opr, Oid typeid, Oid collid,
289 : Datum lhs, Datum rhs);
290 :
291 : static void ri_InitHashTables(void);
292 : static void InvalidateConstraintCacheCallBack(Datum arg, SysCacheIdentifier cacheid,
293 : uint32 hashvalue);
294 : static SPIPlanPtr ri_FetchPreparedPlan(RI_QueryKey *key);
295 : static void ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan);
296 : static RI_CompareHashEntry *ri_HashCompareOp(Oid eq_opr, Oid typeid);
297 :
298 : static void ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname,
299 : int tgkind);
300 : static RI_ConstraintInfo *ri_FetchConstraintInfo(Trigger *trigger,
301 : Relation trig_rel, bool rel_is_pk);
302 : static RI_ConstraintInfo *ri_LoadConstraintInfo(Oid constraintOid);
303 : static Oid get_ri_constraint_root(Oid constrOid);
304 : static SPIPlanPtr ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
305 : RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel);
306 : static bool ri_PerformCheck(const RI_ConstraintInfo *riinfo,
307 : RI_QueryKey *qkey, SPIPlanPtr qplan,
308 : Relation fk_rel, Relation pk_rel,
309 : TupleTableSlot *oldslot, TupleTableSlot *newslot,
310 : bool is_restrict,
311 : bool detectNewRows, int expect_OK);
312 : static void ri_FastPathCheck(RI_ConstraintInfo *riinfo,
313 : Relation fk_rel, TupleTableSlot *newslot);
314 : static void ri_FastPathBatchAdd(RI_ConstraintInfo *riinfo,
315 : Relation fk_rel, TupleTableSlot *newslot);
316 : static void ri_FastPathBatchFlush(RI_FastPathEntry *fpentry, Relation fk_rel,
317 : RI_ConstraintInfo *riinfo);
318 : static int ri_FastPathFlushArray(RI_FastPathEntry *fpentry, TupleTableSlot *fk_slot,
319 : const RI_ConstraintInfo *riinfo, Relation fk_rel,
320 : Snapshot snapshot, IndexScanDesc scandesc);
321 : static int ri_FastPathFlushLoop(RI_FastPathEntry *fpentry, TupleTableSlot *fk_slot,
322 : const RI_ConstraintInfo *riinfo, Relation fk_rel,
323 : Snapshot snapshot, IndexScanDesc scandesc);
324 : static bool ri_FastPathProbeOne(Relation pk_rel, Relation idx_rel,
325 : IndexScanDesc scandesc, TupleTableSlot *slot,
326 : Snapshot snapshot, const RI_ConstraintInfo *riinfo,
327 : ScanKeyData *skey, int nkeys);
328 : static bool ri_LockPKTuple(Relation pk_rel, TupleTableSlot *slot, Snapshot snap,
329 : bool *concurrently_updated);
330 : static bool ri_fastpath_is_applicable(const RI_ConstraintInfo *riinfo);
331 : static void ri_CheckPermissions(Relation query_rel);
332 : static bool recheck_matched_pk_tuple(Relation idxrel, ScanKeyData *skeys,
333 : int nkeys, TupleTableSlot *new_slot);
334 : static void build_index_scankeys(const RI_ConstraintInfo *riinfo,
335 : Relation idx_rel, Datum *pk_vals,
336 : char *pk_nulls, ScanKey skeys);
337 : static void ri_populate_fastpath_metadata(RI_ConstraintInfo *riinfo,
338 : Relation fk_rel, Relation idx_rel);
339 : static void ri_ExtractValues(Relation rel, TupleTableSlot *slot,
340 : const RI_ConstraintInfo *riinfo, bool rel_is_pk,
341 : Datum *vals, char *nulls);
342 : pg_noreturn static void ri_ReportViolation(const RI_ConstraintInfo *riinfo,
343 : Relation pk_rel, Relation fk_rel,
344 : TupleTableSlot *violatorslot, TupleDesc tupdesc,
345 : int queryno, bool is_restrict, bool partgone);
346 : static RI_FastPathEntry *ri_FastPathGetEntry(const RI_ConstraintInfo *riinfo,
347 : Relation fk_rel);
348 : static void ri_FastPathEndBatch(void *arg);
349 : static void ri_FastPathTeardown(void);
350 :
351 :
352 : /*
353 : * RI_FKey_check -
354 : *
355 : * Check foreign key existence (combined for INSERT and UPDATE).
356 : */
357 : static Datum
358 604727 : RI_FKey_check(TriggerData *trigdata)
359 : {
360 : RI_ConstraintInfo *riinfo;
361 : Relation fk_rel;
362 : Relation pk_rel;
363 : TupleTableSlot *newslot;
364 : RI_QueryKey qkey;
365 : SPIPlanPtr qplan;
366 :
367 604727 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
368 : trigdata->tg_relation, false);
369 :
370 604727 : if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
371 294 : newslot = trigdata->tg_newslot;
372 : else
373 604433 : newslot = trigdata->tg_trigslot;
374 :
375 : /*
376 : * We should not even consider checking the row if it is no longer valid,
377 : * since it was either deleted (so the deferred check should be skipped)
378 : * or updated (in which case only the latest version of the row should be
379 : * checked). Test its liveness according to SnapshotSelf. We need pin
380 : * and lock on the buffer to call HeapTupleSatisfiesVisibility. Caller
381 : * should be holding pin, but not lock.
382 : */
383 604727 : if (!table_tuple_satisfies_snapshot(trigdata->tg_relation, newslot, SnapshotSelf))
384 40 : return PointerGetDatum(NULL);
385 :
386 604687 : fk_rel = trigdata->tg_relation;
387 :
388 604687 : switch (ri_NullCheck(RelationGetDescr(fk_rel), newslot, riinfo, false))
389 : {
390 98 : case RI_KEYS_ALL_NULL:
391 :
392 : /*
393 : * No further check needed - an all-NULL key passes every type of
394 : * foreign key constraint.
395 : */
396 98 : return PointerGetDatum(NULL);
397 :
398 104 : case RI_KEYS_SOME_NULL:
399 :
400 : /*
401 : * This is the only case that differs between the three kinds of
402 : * MATCH.
403 : */
404 104 : switch (riinfo->confmatchtype)
405 : {
406 24 : case FKCONSTR_MATCH_FULL:
407 :
408 : /*
409 : * Not allowed - MATCH FULL says either all or none of the
410 : * attributes can be NULLs
411 : */
412 24 : ereport(ERROR,
413 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
414 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
415 : RelationGetRelationName(fk_rel),
416 : NameStr(riinfo->conname)),
417 : errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
418 : errtableconstraint(fk_rel,
419 : NameStr(riinfo->conname))));
420 : return PointerGetDatum(NULL);
421 :
422 80 : case FKCONSTR_MATCH_SIMPLE:
423 :
424 : /*
425 : * MATCH SIMPLE - if ANY column is null, the key passes
426 : * the constraint.
427 : */
428 80 : return PointerGetDatum(NULL);
429 :
430 : #ifdef NOT_USED
431 : case FKCONSTR_MATCH_PARTIAL:
432 :
433 : /*
434 : * MATCH PARTIAL - all non-null columns must match. (not
435 : * implemented, can be done by modifying the query below
436 : * to only include non-null columns, or by writing a
437 : * special version here)
438 : */
439 : break;
440 : #endif
441 : }
442 :
443 : case RI_KEYS_NONE_NULL:
444 :
445 : /*
446 : * Have a full qualified key - continue below for all three kinds
447 : * of MATCH.
448 : */
449 604485 : break;
450 : }
451 :
452 : /*
453 : * Fast path: probe the PK unique index directly, bypassing SPI.
454 : *
455 : * For non-partitioned, non-temporal FKs, we can skip the SPI machinery
456 : * (plan cache, executor setup, etc.) and do a direct index scan + tuple
457 : * lock. This is semantically equivalent to the SPI path below but avoids
458 : * the per-row executor overhead.
459 : *
460 : * ri_FastPathBatchAdd() and ri_FastPathCheck() report the violation
461 : * themselves if no matching PK row is found, so they only return on
462 : * success.
463 : */
464 604485 : if (ri_fastpath_is_applicable(riinfo))
465 : {
466 603695 : if (AfterTriggerIsActive())
467 : {
468 : /* Batched path: buffer and probe in groups */
469 603651 : ri_FastPathBatchAdd(riinfo, fk_rel, newslot);
470 : }
471 : else
472 : {
473 : /* ALTER TABLE validation: per-row, no cache */
474 44 : ri_FastPathCheck(riinfo, fk_rel, newslot);
475 : }
476 603691 : return PointerGetDatum(NULL);
477 : }
478 :
479 790 : SPI_connect();
480 :
481 : /*
482 : * pk_rel is opened in RowShareLock mode since that's what our eventual
483 : * SELECT FOR KEY SHARE will get on it.
484 : */
485 790 : pk_rel = table_open(riinfo->pk_relid, RowShareLock);
486 :
487 : /* Fetch or prepare a saved plan for the real check */
488 790 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK);
489 :
490 790 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
491 : {
492 : StringInfoData querybuf;
493 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
494 : char attname[MAX_QUOTED_NAME_LEN];
495 : char paramname[16];
496 : const char *querysep;
497 : Oid queryoids[RI_MAX_NUMKEYS];
498 : const char *pk_only;
499 :
500 : /* ----------
501 : * The query string built is
502 : * SELECT 1 FROM [ONLY] <pktable> x WHERE pkatt1 = $1 [AND ...]
503 : * FOR KEY SHARE OF x
504 : * The type id's for the $ parameters are those of the
505 : * corresponding FK attributes.
506 : *
507 : * But for temporal FKs we need to make sure
508 : * the FK's range is completely covered.
509 : * So we use this query instead:
510 : * SELECT 1
511 : * FROM (
512 : * SELECT pkperiodatt AS r
513 : * FROM [ONLY] pktable x
514 : * WHERE pkatt1 = $1 [AND ...]
515 : * AND pkperiodatt && $n
516 : * FOR KEY SHARE OF x
517 : * ) x1
518 : * HAVING $n <@ range_agg(x1.r)
519 : * Note if FOR KEY SHARE ever allows GROUP BY and HAVING
520 : * we can make this a bit simpler.
521 : * ----------
522 : */
523 366 : initStringInfo(&querybuf);
524 732 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
525 366 : "" : "ONLY ";
526 366 : quoteRelationName(pkrelname, pk_rel);
527 366 : if (riinfo->hasperiod)
528 : {
529 67 : quoteOneName(attname,
530 67 : RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
531 :
532 67 : appendStringInfo(&querybuf,
533 : "SELECT 1 FROM (SELECT %s AS r FROM %s%s x",
534 : attname, pk_only, pkrelname);
535 : }
536 : else
537 : {
538 299 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
539 : pk_only, pkrelname);
540 : }
541 366 : querysep = "WHERE";
542 815 : for (int i = 0; i < riinfo->nkeys; i++)
543 : {
544 449 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
545 449 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
546 :
547 449 : quoteOneName(attname,
548 449 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
549 449 : sprintf(paramname, "$%d", i + 1);
550 449 : ri_GenerateQual(&querybuf, querysep,
551 : attname, pk_type,
552 : riinfo->pf_eq_oprs[i],
553 : paramname, fk_type);
554 449 : querysep = "AND";
555 449 : queryoids[i] = fk_type;
556 : }
557 366 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
558 366 : if (riinfo->hasperiod)
559 : {
560 67 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
561 :
562 67 : appendStringInfoString(&querybuf, ") x1 HAVING ");
563 67 : sprintf(paramname, "$%d", riinfo->nkeys);
564 67 : ri_GenerateQual(&querybuf, "",
565 : paramname, fk_type,
566 : riinfo->agged_period_contained_by_oper,
567 : "pg_catalog.range_agg", ANYMULTIRANGEOID);
568 67 : appendStringInfoString(&querybuf, "(x1.r)");
569 : }
570 :
571 : /* Prepare and save the plan */
572 366 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
573 : &qkey, fk_rel, pk_rel);
574 : }
575 :
576 : /*
577 : * Now check that foreign key exists in PK table
578 : *
579 : * XXX detectNewRows must be true when a partitioned table is on the
580 : * referenced side. The reason is that our snapshot must be fresh in
581 : * order for the hack in find_inheritance_children() to work.
582 : */
583 790 : ri_PerformCheck(riinfo, &qkey, qplan,
584 : fk_rel, pk_rel,
585 : NULL, newslot,
586 : false,
587 790 : pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE,
588 : SPI_OK_SELECT);
589 :
590 650 : if (SPI_finish() != SPI_OK_FINISH)
591 0 : elog(ERROR, "SPI_finish failed");
592 :
593 650 : table_close(pk_rel, RowShareLock);
594 :
595 650 : return PointerGetDatum(NULL);
596 : }
597 :
598 :
599 : /*
600 : * RI_FKey_check_ins -
601 : *
602 : * Check foreign key existence at insert event on FK table.
603 : */
604 : Datum
605 604433 : RI_FKey_check_ins(PG_FUNCTION_ARGS)
606 : {
607 : /* Check that this is a valid trigger call on the right time and event. */
608 604433 : ri_CheckTrigger(fcinfo, "RI_FKey_check_ins", RI_TRIGTYPE_INSERT);
609 :
610 : /* Share code with UPDATE case. */
611 604433 : return RI_FKey_check((TriggerData *) fcinfo->context);
612 : }
613 :
614 :
615 : /*
616 : * RI_FKey_check_upd -
617 : *
618 : * Check foreign key existence at update event on FK table.
619 : */
620 : Datum
621 294 : RI_FKey_check_upd(PG_FUNCTION_ARGS)
622 : {
623 : /* Check that this is a valid trigger call on the right time and event. */
624 294 : ri_CheckTrigger(fcinfo, "RI_FKey_check_upd", RI_TRIGTYPE_UPDATE);
625 :
626 : /* Share code with INSERT case. */
627 294 : return RI_FKey_check((TriggerData *) fcinfo->context);
628 : }
629 :
630 :
631 : /*
632 : * ri_Check_Pk_Match
633 : *
634 : * Check to see if another PK row has been created that provides the same
635 : * key values as the "oldslot" that's been modified or deleted in our trigger
636 : * event. Returns true if a match is found in the PK table.
637 : *
638 : * We assume the caller checked that the oldslot contains no NULL key values,
639 : * since otherwise a match is impossible.
640 : */
641 : static bool
642 523 : ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
643 : TupleTableSlot *oldslot,
644 : const RI_ConstraintInfo *riinfo)
645 : {
646 : SPIPlanPtr qplan;
647 : RI_QueryKey qkey;
648 : bool result;
649 :
650 : /* Only called for non-null rows */
651 : Assert(ri_NullCheck(RelationGetDescr(pk_rel), oldslot, riinfo, true) == RI_KEYS_NONE_NULL);
652 :
653 523 : SPI_connect();
654 :
655 : /*
656 : * Fetch or prepare a saved plan for checking PK table with values coming
657 : * from a PK row
658 : */
659 523 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK_FROM_PK);
660 :
661 523 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
662 : {
663 : StringInfoData querybuf;
664 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
665 : char attname[MAX_QUOTED_NAME_LEN];
666 : char paramname[16];
667 : const char *querysep;
668 : const char *pk_only;
669 : Oid queryoids[RI_MAX_NUMKEYS];
670 :
671 : /* ----------
672 : * The query string built is
673 : * SELECT 1 FROM [ONLY] <pktable> x WHERE pkatt1 = $1 [AND ...]
674 : * FOR KEY SHARE OF x
675 : * The type id's for the $ parameters are those of the
676 : * PK attributes themselves.
677 : *
678 : * But for temporal FKs we need to make sure
679 : * the old PK's range is completely covered.
680 : * So we use this query instead:
681 : * SELECT 1
682 : * FROM (
683 : * SELECT pkperiodatt AS r
684 : * FROM [ONLY] pktable x
685 : * WHERE pkatt1 = $1 [AND ...]
686 : * AND pkperiodatt && $n
687 : * FOR KEY SHARE OF x
688 : * ) x1
689 : * HAVING $n <@ range_agg(x1.r)
690 : * Note if FOR KEY SHARE ever allows GROUP BY and HAVING
691 : * we can make this a bit simpler.
692 : * ----------
693 : */
694 258 : initStringInfo(&querybuf);
695 516 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
696 258 : "" : "ONLY ";
697 258 : quoteRelationName(pkrelname, pk_rel);
698 258 : if (riinfo->hasperiod)
699 : {
700 0 : quoteOneName(attname, RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
701 :
702 0 : appendStringInfo(&querybuf,
703 : "SELECT 1 FROM (SELECT %s AS r FROM %s%s x",
704 : attname, pk_only, pkrelname);
705 : }
706 : else
707 : {
708 258 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
709 : pk_only, pkrelname);
710 : }
711 258 : querysep = "WHERE";
712 600 : for (int i = 0; i < riinfo->nkeys; i++)
713 : {
714 342 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
715 :
716 342 : quoteOneName(attname,
717 342 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
718 342 : sprintf(paramname, "$%d", i + 1);
719 342 : ri_GenerateQual(&querybuf, querysep,
720 : attname, pk_type,
721 342 : riinfo->pp_eq_oprs[i],
722 : paramname, pk_type);
723 342 : querysep = "AND";
724 342 : queryoids[i] = pk_type;
725 : }
726 258 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
727 258 : if (riinfo->hasperiod)
728 : {
729 0 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
730 :
731 0 : appendStringInfoString(&querybuf, ") x1 HAVING ");
732 0 : sprintf(paramname, "$%d", riinfo->nkeys);
733 0 : ri_GenerateQual(&querybuf, "",
734 : paramname, fk_type,
735 0 : riinfo->agged_period_contained_by_oper,
736 : "pg_catalog.range_agg", ANYMULTIRANGEOID);
737 0 : appendStringInfoString(&querybuf, "(x1.r)");
738 : }
739 :
740 : /* Prepare and save the plan */
741 258 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
742 : &qkey, fk_rel, pk_rel);
743 : }
744 :
745 : /*
746 : * We have a plan now. Run it.
747 : */
748 523 : result = ri_PerformCheck(riinfo, &qkey, qplan,
749 : fk_rel, pk_rel,
750 : oldslot, NULL,
751 : false,
752 : true, /* treat like update */
753 : SPI_OK_SELECT);
754 :
755 523 : if (SPI_finish() != SPI_OK_FINISH)
756 0 : elog(ERROR, "SPI_finish failed");
757 :
758 523 : return result;
759 : }
760 :
761 :
762 : /*
763 : * RI_FKey_noaction_del -
764 : *
765 : * Give an error and roll back the current transaction if the
766 : * delete has resulted in a violation of the given referential
767 : * integrity constraint.
768 : */
769 : Datum
770 313 : RI_FKey_noaction_del(PG_FUNCTION_ARGS)
771 : {
772 : /* Check that this is a valid trigger call on the right time and event. */
773 313 : ri_CheckTrigger(fcinfo, "RI_FKey_noaction_del", RI_TRIGTYPE_DELETE);
774 :
775 : /* Share code with RESTRICT/UPDATE cases. */
776 313 : return ri_restrict((TriggerData *) fcinfo->context, true);
777 : }
778 :
779 : /*
780 : * RI_FKey_restrict_del -
781 : *
782 : * Restrict delete from PK table to rows unreferenced by foreign key.
783 : *
784 : * The SQL standard intends that this referential action occur exactly when
785 : * the delete is performed, rather than after. This appears to be
786 : * the only difference between "NO ACTION" and "RESTRICT". In Postgres
787 : * we still implement this as an AFTER trigger, but it's non-deferrable.
788 : */
789 : Datum
790 8 : RI_FKey_restrict_del(PG_FUNCTION_ARGS)
791 : {
792 : /* Check that this is a valid trigger call on the right time and event. */
793 8 : ri_CheckTrigger(fcinfo, "RI_FKey_restrict_del", RI_TRIGTYPE_DELETE);
794 :
795 : /* Share code with NO ACTION/UPDATE cases. */
796 8 : return ri_restrict((TriggerData *) fcinfo->context, false);
797 : }
798 :
799 : /*
800 : * RI_FKey_noaction_upd -
801 : *
802 : * Give an error and roll back the current transaction if the
803 : * update has resulted in a violation of the given referential
804 : * integrity constraint.
805 : */
806 : Datum
807 356 : RI_FKey_noaction_upd(PG_FUNCTION_ARGS)
808 : {
809 : /* Check that this is a valid trigger call on the right time and event. */
810 356 : ri_CheckTrigger(fcinfo, "RI_FKey_noaction_upd", RI_TRIGTYPE_UPDATE);
811 :
812 : /* Share code with RESTRICT/DELETE cases. */
813 356 : return ri_restrict((TriggerData *) fcinfo->context, true);
814 : }
815 :
816 : /*
817 : * RI_FKey_restrict_upd -
818 : *
819 : * Restrict update of PK to rows unreferenced by foreign key.
820 : *
821 : * The SQL standard intends that this referential action occur exactly when
822 : * the update is performed, rather than after. This appears to be
823 : * the only difference between "NO ACTION" and "RESTRICT". In Postgres
824 : * we still implement this as an AFTER trigger, but it's non-deferrable.
825 : */
826 : Datum
827 20 : RI_FKey_restrict_upd(PG_FUNCTION_ARGS)
828 : {
829 : /* Check that this is a valid trigger call on the right time and event. */
830 20 : ri_CheckTrigger(fcinfo, "RI_FKey_restrict_upd", RI_TRIGTYPE_UPDATE);
831 :
832 : /* Share code with NO ACTION/DELETE cases. */
833 20 : return ri_restrict((TriggerData *) fcinfo->context, false);
834 : }
835 :
836 : /*
837 : * ri_restrict -
838 : *
839 : * Common code for ON DELETE RESTRICT, ON DELETE NO ACTION,
840 : * ON UPDATE RESTRICT, and ON UPDATE NO ACTION.
841 : */
842 : static Datum
843 785 : ri_restrict(TriggerData *trigdata, bool is_no_action)
844 : {
845 : const RI_ConstraintInfo *riinfo;
846 : Relation fk_rel;
847 : Relation pk_rel;
848 : TupleTableSlot *oldslot;
849 : RI_QueryKey qkey;
850 : SPIPlanPtr qplan;
851 :
852 785 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
853 : trigdata->tg_relation, true);
854 :
855 : /*
856 : * Get the relation descriptors of the FK and PK tables and the old tuple.
857 : *
858 : * fk_rel is opened in RowShareLock mode since that's what our eventual
859 : * SELECT FOR KEY SHARE will get on it.
860 : */
861 785 : fk_rel = table_open(riinfo->fk_relid, RowShareLock);
862 785 : pk_rel = trigdata->tg_relation;
863 785 : oldslot = trigdata->tg_trigslot;
864 :
865 : /*
866 : * If another PK row now exists providing the old key values, we should
867 : * not do anything. However, this check should only be made in the NO
868 : * ACTION case; in RESTRICT cases we don't wish to allow another row to be
869 : * substituted.
870 : *
871 : * If the foreign key has PERIOD, we incorporate looking for replacement
872 : * rows in the main SQL query below, so we needn't do it here.
873 : */
874 1308 : if (is_no_action && !riinfo->hasperiod &&
875 523 : ri_Check_Pk_Match(pk_rel, fk_rel, oldslot, riinfo))
876 : {
877 38 : table_close(fk_rel, RowShareLock);
878 38 : return PointerGetDatum(NULL);
879 : }
880 :
881 747 : SPI_connect();
882 :
883 : /*
884 : * Fetch or prepare a saved plan for the restrict lookup (it's the same
885 : * query for delete and update cases)
886 : */
887 747 : ri_BuildQueryKey(&qkey, riinfo, is_no_action ? RI_PLAN_NO_ACTION : RI_PLAN_RESTRICT);
888 :
889 747 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
890 : {
891 : StringInfoData querybuf;
892 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
893 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
894 : char attname[MAX_QUOTED_NAME_LEN];
895 : char periodattname[MAX_QUOTED_NAME_LEN];
896 : char paramname[16];
897 : const char *querysep;
898 : Oid queryoids[RI_MAX_NUMKEYS];
899 : const char *fk_only;
900 :
901 : /* ----------
902 : * The query string built is
903 : * SELECT 1 FROM [ONLY] <fktable> x WHERE $1 = fkatt1 [AND ...]
904 : * FOR KEY SHARE OF x
905 : * The type id's for the $ parameters are those of the
906 : * corresponding PK attributes.
907 : * ----------
908 : */
909 318 : initStringInfo(&querybuf);
910 636 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
911 318 : "" : "ONLY ";
912 318 : quoteRelationName(fkrelname, fk_rel);
913 318 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
914 : fk_only, fkrelname);
915 318 : querysep = "WHERE";
916 811 : for (int i = 0; i < riinfo->nkeys; i++)
917 : {
918 493 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
919 493 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
920 :
921 493 : quoteOneName(attname,
922 493 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
923 493 : sprintf(paramname, "$%d", i + 1);
924 493 : ri_GenerateQual(&querybuf, querysep,
925 : paramname, pk_type,
926 493 : riinfo->pf_eq_oprs[i],
927 : attname, fk_type);
928 493 : querysep = "AND";
929 493 : queryoids[i] = pk_type;
930 : }
931 :
932 : /*----------
933 : * For temporal foreign keys, a reference could still be valid if the
934 : * referenced range didn't change too much. Also if a referencing
935 : * range extends past the current PK row, we don't want to check that
936 : * part: some other PK row should fulfill it. We only want to check
937 : * the part matching the PK record we've changed. Therefore to find
938 : * invalid records we do this:
939 : *
940 : * SELECT 1 FROM [ONLY] <fktable> x WHERE $1 = x.fkatt1 [AND ...]
941 : * -- begin temporal
942 : * AND $n && x.fkperiod
943 : * AND NOT coalesce((x.fkperiod * $n) <@
944 : * (SELECT range_agg(r)
945 : * FROM (SELECT y.pkperiod r
946 : * FROM [ONLY] <pktable> y
947 : * WHERE $1 = y.pkatt1 [AND ...] AND $n && y.pkperiod
948 : * FOR KEY SHARE OF y) y2), false)
949 : * -- end temporal
950 : * FOR KEY SHARE OF x
951 : *
952 : * We need the coalesce in case the first subquery returns no rows.
953 : * We need the second subquery because FOR KEY SHARE doesn't support
954 : * aggregate queries.
955 : */
956 318 : if (riinfo->hasperiod && is_no_action)
957 : {
958 91 : Oid pk_period_type = RIAttType(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]);
959 91 : Oid fk_period_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
960 : StringInfoData intersectbuf;
961 : StringInfoData replacementsbuf;
962 182 : char *pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
963 91 : "" : "ONLY ";
964 :
965 91 : quoteOneName(attname, RIAttName(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]));
966 91 : sprintf(paramname, "$%d", riinfo->nkeys);
967 :
968 91 : appendStringInfoString(&querybuf, " AND NOT coalesce(");
969 :
970 : /* Intersect the fk with the old pk range */
971 91 : initStringInfo(&intersectbuf);
972 91 : appendStringInfoChar(&intersectbuf, '(');
973 91 : ri_GenerateQual(&intersectbuf, "",
974 : attname, fk_period_type,
975 91 : riinfo->period_intersect_oper,
976 : paramname, pk_period_type);
977 91 : appendStringInfoChar(&intersectbuf, ')');
978 :
979 : /* Find the remaining history */
980 91 : initStringInfo(&replacementsbuf);
981 91 : appendStringInfoString(&replacementsbuf, "(SELECT pg_catalog.range_agg(r) FROM ");
982 :
983 91 : quoteOneName(periodattname, RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
984 91 : quoteRelationName(pkrelname, pk_rel);
985 91 : appendStringInfo(&replacementsbuf, "(SELECT y.%s r FROM %s%s y",
986 : periodattname, pk_only, pkrelname);
987 :
988 : /* Restrict pk rows to what matches */
989 91 : querysep = "WHERE";
990 273 : for (int i = 0; i < riinfo->nkeys; i++)
991 : {
992 182 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
993 :
994 182 : quoteOneName(attname,
995 182 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
996 182 : sprintf(paramname, "$%d", i + 1);
997 182 : ri_GenerateQual(&replacementsbuf, querysep,
998 : paramname, pk_type,
999 182 : riinfo->pp_eq_oprs[i],
1000 : attname, pk_type);
1001 182 : querysep = "AND";
1002 182 : queryoids[i] = pk_type;
1003 : }
1004 91 : appendStringInfoString(&replacementsbuf, " FOR KEY SHARE OF y) y2)");
1005 :
1006 91 : ri_GenerateQual(&querybuf, "",
1007 91 : intersectbuf.data, fk_period_type,
1008 91 : riinfo->agged_period_contained_by_oper,
1009 91 : replacementsbuf.data, ANYMULTIRANGEOID);
1010 : /* end of coalesce: */
1011 91 : appendStringInfoString(&querybuf, ", false)");
1012 : }
1013 :
1014 318 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
1015 :
1016 : /* Prepare and save the plan */
1017 318 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
1018 : &qkey, fk_rel, pk_rel);
1019 : }
1020 :
1021 : /*
1022 : * We have a plan now. Run it to check for existing references.
1023 : */
1024 747 : ri_PerformCheck(riinfo, &qkey, qplan,
1025 : fk_rel, pk_rel,
1026 : oldslot, NULL,
1027 : !is_no_action,
1028 : true, /* must detect new rows */
1029 747 : SPI_OK_SELECT);
1030 :
1031 417 : if (SPI_finish() != SPI_OK_FINISH)
1032 0 : elog(ERROR, "SPI_finish failed");
1033 :
1034 417 : table_close(fk_rel, RowShareLock);
1035 :
1036 417 : return PointerGetDatum(NULL);
1037 : }
1038 :
1039 :
1040 : /*
1041 : * RI_FKey_cascade_del -
1042 : *
1043 : * Cascaded delete foreign key references at delete event on PK table.
1044 : */
1045 : Datum
1046 98 : RI_FKey_cascade_del(PG_FUNCTION_ARGS)
1047 : {
1048 98 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
1049 : const RI_ConstraintInfo *riinfo;
1050 : Relation fk_rel;
1051 : Relation pk_rel;
1052 : TupleTableSlot *oldslot;
1053 : RI_QueryKey qkey;
1054 : SPIPlanPtr qplan;
1055 :
1056 : /* Check that this is a valid trigger call on the right time and event. */
1057 98 : ri_CheckTrigger(fcinfo, "RI_FKey_cascade_del", RI_TRIGTYPE_DELETE);
1058 :
1059 98 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
1060 : trigdata->tg_relation, true);
1061 :
1062 : /*
1063 : * Get the relation descriptors of the FK and PK tables and the old tuple.
1064 : *
1065 : * fk_rel is opened in RowExclusiveLock mode since that's what our
1066 : * eventual DELETE will get on it.
1067 : */
1068 98 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
1069 98 : pk_rel = trigdata->tg_relation;
1070 98 : oldslot = trigdata->tg_trigslot;
1071 :
1072 98 : SPI_connect();
1073 :
1074 : /* Fetch or prepare a saved plan for the cascaded delete */
1075 98 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_ONDELETE);
1076 :
1077 98 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
1078 : {
1079 : StringInfoData querybuf;
1080 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1081 : char attname[MAX_QUOTED_NAME_LEN];
1082 : char paramname[16];
1083 : const char *querysep;
1084 : Oid queryoids[RI_MAX_NUMKEYS];
1085 : const char *fk_only;
1086 :
1087 : /* ----------
1088 : * The query string built is
1089 : * DELETE FROM [ONLY] <fktable> WHERE $1 = fkatt1 [AND ...]
1090 : * The type id's for the $ parameters are those of the
1091 : * corresponding PK attributes.
1092 : * ----------
1093 : */
1094 58 : initStringInfo(&querybuf);
1095 116 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1096 58 : "" : "ONLY ";
1097 58 : quoteRelationName(fkrelname, fk_rel);
1098 58 : appendStringInfo(&querybuf, "DELETE FROM %s%s",
1099 : fk_only, fkrelname);
1100 58 : querysep = "WHERE";
1101 128 : for (int i = 0; i < riinfo->nkeys; i++)
1102 : {
1103 70 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1104 70 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1105 :
1106 70 : quoteOneName(attname,
1107 70 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1108 70 : sprintf(paramname, "$%d", i + 1);
1109 70 : ri_GenerateQual(&querybuf, querysep,
1110 : paramname, pk_type,
1111 70 : riinfo->pf_eq_oprs[i],
1112 : attname, fk_type);
1113 70 : querysep = "AND";
1114 70 : queryoids[i] = pk_type;
1115 : }
1116 :
1117 : /* Prepare and save the plan */
1118 58 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
1119 : &qkey, fk_rel, pk_rel);
1120 : }
1121 :
1122 : /*
1123 : * We have a plan now. Build up the arguments from the key values in the
1124 : * deleted PK tuple and delete the referencing rows
1125 : */
1126 98 : ri_PerformCheck(riinfo, &qkey, qplan,
1127 : fk_rel, pk_rel,
1128 : oldslot, NULL,
1129 : false,
1130 : true, /* must detect new rows */
1131 : SPI_OK_DELETE);
1132 :
1133 97 : if (SPI_finish() != SPI_OK_FINISH)
1134 0 : elog(ERROR, "SPI_finish failed");
1135 :
1136 97 : table_close(fk_rel, RowExclusiveLock);
1137 :
1138 97 : return PointerGetDatum(NULL);
1139 : }
1140 :
1141 :
1142 : /*
1143 : * RI_FKey_cascade_upd -
1144 : *
1145 : * Cascaded update foreign key references at update event on PK table.
1146 : */
1147 : Datum
1148 144 : RI_FKey_cascade_upd(PG_FUNCTION_ARGS)
1149 : {
1150 144 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
1151 : const RI_ConstraintInfo *riinfo;
1152 : Relation fk_rel;
1153 : Relation pk_rel;
1154 : TupleTableSlot *newslot;
1155 : TupleTableSlot *oldslot;
1156 : RI_QueryKey qkey;
1157 : SPIPlanPtr qplan;
1158 :
1159 : /* Check that this is a valid trigger call on the right time and event. */
1160 144 : ri_CheckTrigger(fcinfo, "RI_FKey_cascade_upd", RI_TRIGTYPE_UPDATE);
1161 :
1162 144 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
1163 : trigdata->tg_relation, true);
1164 :
1165 : /*
1166 : * Get the relation descriptors of the FK and PK tables and the new and
1167 : * old tuple.
1168 : *
1169 : * fk_rel is opened in RowExclusiveLock mode since that's what our
1170 : * eventual UPDATE will get on it.
1171 : */
1172 144 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
1173 144 : pk_rel = trigdata->tg_relation;
1174 144 : newslot = trigdata->tg_newslot;
1175 144 : oldslot = trigdata->tg_trigslot;
1176 :
1177 144 : SPI_connect();
1178 :
1179 : /* Fetch or prepare a saved plan for the cascaded update */
1180 144 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_ONUPDATE);
1181 :
1182 144 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
1183 : {
1184 : StringInfoData querybuf;
1185 : StringInfoData qualbuf;
1186 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1187 : char attname[MAX_QUOTED_NAME_LEN];
1188 : char paramname[16];
1189 : const char *querysep;
1190 : const char *qualsep;
1191 : Oid queryoids[RI_MAX_NUMKEYS * 2];
1192 : const char *fk_only;
1193 :
1194 : /* ----------
1195 : * The query string built is
1196 : * UPDATE [ONLY] <fktable> SET fkatt1 = $1 [, ...]
1197 : * WHERE $n = fkatt1 [AND ...]
1198 : * The type id's for the $ parameters are those of the
1199 : * corresponding PK attributes. Note that we are assuming
1200 : * there is an assignment cast from the PK to the FK type;
1201 : * else the parser will fail.
1202 : * ----------
1203 : */
1204 85 : initStringInfo(&querybuf);
1205 85 : initStringInfo(&qualbuf);
1206 170 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1207 85 : "" : "ONLY ";
1208 85 : quoteRelationName(fkrelname, fk_rel);
1209 85 : appendStringInfo(&querybuf, "UPDATE %s%s SET",
1210 : fk_only, fkrelname);
1211 85 : querysep = "";
1212 85 : qualsep = "WHERE";
1213 188 : for (int i = 0, j = riinfo->nkeys; i < riinfo->nkeys; i++, j++)
1214 : {
1215 103 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1216 103 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1217 :
1218 103 : quoteOneName(attname,
1219 103 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1220 103 : appendStringInfo(&querybuf,
1221 : "%s %s = $%d",
1222 : querysep, attname, i + 1);
1223 103 : sprintf(paramname, "$%d", j + 1);
1224 103 : ri_GenerateQual(&qualbuf, qualsep,
1225 : paramname, pk_type,
1226 103 : riinfo->pf_eq_oprs[i],
1227 : attname, fk_type);
1228 103 : querysep = ",";
1229 103 : qualsep = "AND";
1230 103 : queryoids[i] = pk_type;
1231 103 : queryoids[j] = pk_type;
1232 : }
1233 85 : appendBinaryStringInfo(&querybuf, qualbuf.data, qualbuf.len);
1234 :
1235 : /* Prepare and save the plan */
1236 85 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys * 2, queryoids,
1237 : &qkey, fk_rel, pk_rel);
1238 : }
1239 :
1240 : /*
1241 : * We have a plan now. Run it to update the existing references.
1242 : */
1243 144 : ri_PerformCheck(riinfo, &qkey, qplan,
1244 : fk_rel, pk_rel,
1245 : oldslot, newslot,
1246 : false,
1247 : true, /* must detect new rows */
1248 : SPI_OK_UPDATE);
1249 :
1250 144 : if (SPI_finish() != SPI_OK_FINISH)
1251 0 : elog(ERROR, "SPI_finish failed");
1252 :
1253 144 : table_close(fk_rel, RowExclusiveLock);
1254 :
1255 144 : return PointerGetDatum(NULL);
1256 : }
1257 :
1258 :
1259 : /*
1260 : * RI_FKey_setnull_del -
1261 : *
1262 : * Set foreign key references to NULL values at delete event on PK table.
1263 : */
1264 : Datum
1265 65 : RI_FKey_setnull_del(PG_FUNCTION_ARGS)
1266 : {
1267 : /* Check that this is a valid trigger call on the right time and event. */
1268 65 : ri_CheckTrigger(fcinfo, "RI_FKey_setnull_del", RI_TRIGTYPE_DELETE);
1269 :
1270 : /* Share code with UPDATE case */
1271 65 : return ri_set((TriggerData *) fcinfo->context, true, RI_TRIGTYPE_DELETE);
1272 : }
1273 :
1274 : /*
1275 : * RI_FKey_setnull_upd -
1276 : *
1277 : * Set foreign key references to NULL at update event on PK table.
1278 : */
1279 : Datum
1280 20 : RI_FKey_setnull_upd(PG_FUNCTION_ARGS)
1281 : {
1282 : /* Check that this is a valid trigger call on the right time and event. */
1283 20 : ri_CheckTrigger(fcinfo, "RI_FKey_setnull_upd", RI_TRIGTYPE_UPDATE);
1284 :
1285 : /* Share code with DELETE case */
1286 20 : return ri_set((TriggerData *) fcinfo->context, true, RI_TRIGTYPE_UPDATE);
1287 : }
1288 :
1289 : /*
1290 : * RI_FKey_setdefault_del -
1291 : *
1292 : * Set foreign key references to defaults at delete event on PK table.
1293 : */
1294 : Datum
1295 56 : RI_FKey_setdefault_del(PG_FUNCTION_ARGS)
1296 : {
1297 : /* Check that this is a valid trigger call on the right time and event. */
1298 56 : ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_del", RI_TRIGTYPE_DELETE);
1299 :
1300 : /* Share code with UPDATE case */
1301 56 : return ri_set((TriggerData *) fcinfo->context, false, RI_TRIGTYPE_DELETE);
1302 : }
1303 :
1304 : /*
1305 : * RI_FKey_setdefault_upd -
1306 : *
1307 : * Set foreign key references to defaults at update event on PK table.
1308 : */
1309 : Datum
1310 32 : RI_FKey_setdefault_upd(PG_FUNCTION_ARGS)
1311 : {
1312 : /* Check that this is a valid trigger call on the right time and event. */
1313 32 : ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_upd", RI_TRIGTYPE_UPDATE);
1314 :
1315 : /* Share code with DELETE case */
1316 32 : return ri_set((TriggerData *) fcinfo->context, false, RI_TRIGTYPE_UPDATE);
1317 : }
1318 :
1319 : /*
1320 : * ri_set -
1321 : *
1322 : * Common code for ON DELETE SET NULL, ON DELETE SET DEFAULT, ON UPDATE SET
1323 : * NULL, and ON UPDATE SET DEFAULT.
1324 : */
1325 : static Datum
1326 173 : ri_set(TriggerData *trigdata, bool is_set_null, int tgkind)
1327 : {
1328 : const RI_ConstraintInfo *riinfo;
1329 : Relation fk_rel;
1330 : Relation pk_rel;
1331 : TupleTableSlot *oldslot;
1332 : RI_QueryKey qkey;
1333 : SPIPlanPtr qplan;
1334 : int32 queryno;
1335 :
1336 173 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
1337 : trigdata->tg_relation, true);
1338 :
1339 : /*
1340 : * Get the relation descriptors of the FK and PK tables and the old tuple.
1341 : *
1342 : * fk_rel is opened in RowExclusiveLock mode since that's what our
1343 : * eventual UPDATE will get on it.
1344 : */
1345 173 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
1346 173 : pk_rel = trigdata->tg_relation;
1347 173 : oldslot = trigdata->tg_trigslot;
1348 :
1349 173 : SPI_connect();
1350 :
1351 : /*
1352 : * Fetch or prepare a saved plan for the trigger.
1353 : */
1354 173 : switch (tgkind)
1355 : {
1356 52 : case RI_TRIGTYPE_UPDATE:
1357 52 : queryno = is_set_null
1358 : ? RI_PLAN_SETNULL_ONUPDATE
1359 52 : : RI_PLAN_SETDEFAULT_ONUPDATE;
1360 52 : break;
1361 121 : case RI_TRIGTYPE_DELETE:
1362 121 : queryno = is_set_null
1363 : ? RI_PLAN_SETNULL_ONDELETE
1364 121 : : RI_PLAN_SETDEFAULT_ONDELETE;
1365 121 : break;
1366 0 : default:
1367 0 : elog(ERROR, "invalid tgkind passed to ri_set");
1368 : }
1369 :
1370 173 : ri_BuildQueryKey(&qkey, riinfo, queryno);
1371 :
1372 173 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
1373 : {
1374 : StringInfoData querybuf;
1375 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1376 : char attname[MAX_QUOTED_NAME_LEN];
1377 : char paramname[16];
1378 : const char *querysep;
1379 : const char *qualsep;
1380 : Oid queryoids[RI_MAX_NUMKEYS];
1381 : const char *fk_only;
1382 : int num_cols_to_set;
1383 : const int16 *set_cols;
1384 :
1385 103 : switch (tgkind)
1386 : {
1387 32 : case RI_TRIGTYPE_UPDATE:
1388 32 : num_cols_to_set = riinfo->nkeys;
1389 32 : set_cols = riinfo->fk_attnums;
1390 32 : break;
1391 71 : case RI_TRIGTYPE_DELETE:
1392 :
1393 : /*
1394 : * If confdelsetcols are present, then we only update the
1395 : * columns specified in that array, otherwise we update all
1396 : * the referencing columns.
1397 : */
1398 71 : if (riinfo->ndelsetcols != 0)
1399 : {
1400 16 : num_cols_to_set = riinfo->ndelsetcols;
1401 16 : set_cols = riinfo->confdelsetcols;
1402 : }
1403 : else
1404 : {
1405 55 : num_cols_to_set = riinfo->nkeys;
1406 55 : set_cols = riinfo->fk_attnums;
1407 : }
1408 71 : break;
1409 0 : default:
1410 0 : elog(ERROR, "invalid tgkind passed to ri_set");
1411 : }
1412 :
1413 : /* ----------
1414 : * The query string built is
1415 : * UPDATE [ONLY] <fktable> SET fkatt1 = {NULL|DEFAULT} [, ...]
1416 : * WHERE $1 = fkatt1 [AND ...]
1417 : * The type id's for the $ parameters are those of the
1418 : * corresponding PK attributes.
1419 : * ----------
1420 : */
1421 103 : initStringInfo(&querybuf);
1422 206 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1423 103 : "" : "ONLY ";
1424 103 : quoteRelationName(fkrelname, fk_rel);
1425 103 : appendStringInfo(&querybuf, "UPDATE %s%s SET",
1426 : fk_only, fkrelname);
1427 :
1428 : /*
1429 : * Add assignment clauses
1430 : */
1431 103 : querysep = "";
1432 273 : for (int i = 0; i < num_cols_to_set; i++)
1433 : {
1434 170 : quoteOneName(attname, RIAttName(fk_rel, set_cols[i]));
1435 170 : appendStringInfo(&querybuf,
1436 : "%s %s = %s",
1437 : querysep, attname,
1438 : is_set_null ? "NULL" : "DEFAULT");
1439 170 : querysep = ",";
1440 : }
1441 :
1442 : /*
1443 : * Add WHERE clause
1444 : */
1445 103 : qualsep = "WHERE";
1446 289 : for (int i = 0; i < riinfo->nkeys; i++)
1447 : {
1448 186 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1449 186 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1450 :
1451 186 : quoteOneName(attname,
1452 186 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1453 :
1454 186 : sprintf(paramname, "$%d", i + 1);
1455 186 : ri_GenerateQual(&querybuf, qualsep,
1456 : paramname, pk_type,
1457 186 : riinfo->pf_eq_oprs[i],
1458 : attname, fk_type);
1459 186 : qualsep = "AND";
1460 186 : queryoids[i] = pk_type;
1461 : }
1462 :
1463 : /* Prepare and save the plan */
1464 103 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
1465 : &qkey, fk_rel, pk_rel);
1466 : }
1467 :
1468 : /*
1469 : * We have a plan now. Run it to update the existing references.
1470 : */
1471 173 : ri_PerformCheck(riinfo, &qkey, qplan,
1472 : fk_rel, pk_rel,
1473 : oldslot, NULL,
1474 : false,
1475 : true, /* must detect new rows */
1476 : SPI_OK_UPDATE);
1477 :
1478 172 : if (SPI_finish() != SPI_OK_FINISH)
1479 0 : elog(ERROR, "SPI_finish failed");
1480 :
1481 172 : table_close(fk_rel, RowExclusiveLock);
1482 :
1483 172 : if (is_set_null)
1484 84 : return PointerGetDatum(NULL);
1485 : else
1486 : {
1487 : /*
1488 : * If we just deleted or updated the PK row whose key was equal to the
1489 : * FK columns' default values, and a referencing row exists in the FK
1490 : * table, we would have updated that row to the same values it already
1491 : * had --- and RI_FKey_fk_upd_check_required would hence believe no
1492 : * check is necessary. So we need to do another lookup now and in
1493 : * case a reference still exists, abort the operation. That is
1494 : * already implemented in the NO ACTION trigger, so just run it. (This
1495 : * recheck is only needed in the SET DEFAULT case, since CASCADE would
1496 : * remove such rows in case of a DELETE operation or would change the
1497 : * FK key values in case of an UPDATE, while SET NULL is certain to
1498 : * result in rows that satisfy the FK constraint.)
1499 : */
1500 88 : return ri_restrict(trigdata, true);
1501 : }
1502 : }
1503 :
1504 :
1505 : /*
1506 : * RI_FKey_pk_upd_check_required -
1507 : *
1508 : * Check if we really need to fire the RI trigger for an update or delete to a PK
1509 : * relation. This is called by the AFTER trigger queue manager to see if
1510 : * it can skip queuing an instance of an RI trigger. Returns true if the
1511 : * trigger must be fired, false if we can prove the constraint will still
1512 : * be satisfied.
1513 : *
1514 : * newslot will be NULL if this is called for a delete.
1515 : */
1516 : bool
1517 1533 : RI_FKey_pk_upd_check_required(Trigger *trigger, Relation pk_rel,
1518 : TupleTableSlot *oldslot, TupleTableSlot *newslot)
1519 : {
1520 : const RI_ConstraintInfo *riinfo;
1521 :
1522 1533 : riinfo = ri_FetchConstraintInfo(trigger, pk_rel, true);
1523 :
1524 : /*
1525 : * If any old key value is NULL, the row could not have been referenced by
1526 : * an FK row, so no check is needed.
1527 : */
1528 1533 : if (ri_NullCheck(RelationGetDescr(pk_rel), oldslot, riinfo, true) != RI_KEYS_NONE_NULL)
1529 4 : return false;
1530 :
1531 : /* If all old and new key values are equal, no check is needed */
1532 1529 : if (newslot && ri_KeysEqual(pk_rel, oldslot, newslot, riinfo, true))
1533 288 : return false;
1534 :
1535 : /* Else we need to fire the trigger. */
1536 1241 : return true;
1537 : }
1538 :
1539 : /*
1540 : * RI_FKey_fk_upd_check_required -
1541 : *
1542 : * Check if we really need to fire the RI trigger for an update to an FK
1543 : * relation. This is called by the AFTER trigger queue manager to see if
1544 : * it can skip queuing an instance of an RI trigger. Returns true if the
1545 : * trigger must be fired, false if we can prove the constraint will still
1546 : * be satisfied.
1547 : */
1548 : bool
1549 668 : RI_FKey_fk_upd_check_required(Trigger *trigger, Relation fk_rel,
1550 : TupleTableSlot *oldslot, TupleTableSlot *newslot)
1551 : {
1552 : const RI_ConstraintInfo *riinfo;
1553 : int ri_nullcheck;
1554 :
1555 : /*
1556 : * AfterTriggerSaveEvent() handles things such that this function is never
1557 : * called for partitioned tables.
1558 : */
1559 : Assert(fk_rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE);
1560 :
1561 668 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1562 :
1563 668 : ri_nullcheck = ri_NullCheck(RelationGetDescr(fk_rel), newslot, riinfo, false);
1564 :
1565 : /*
1566 : * If all new key values are NULL, the row satisfies the constraint, so no
1567 : * check is needed.
1568 : */
1569 668 : if (ri_nullcheck == RI_KEYS_ALL_NULL)
1570 84 : return false;
1571 :
1572 : /*
1573 : * If some new key values are NULL, the behavior depends on the match
1574 : * type.
1575 : */
1576 584 : else if (ri_nullcheck == RI_KEYS_SOME_NULL)
1577 : {
1578 20 : switch (riinfo->confmatchtype)
1579 : {
1580 16 : case FKCONSTR_MATCH_SIMPLE:
1581 :
1582 : /*
1583 : * If any new key value is NULL, the row must satisfy the
1584 : * constraint, so no check is needed.
1585 : */
1586 16 : return false;
1587 :
1588 0 : case FKCONSTR_MATCH_PARTIAL:
1589 :
1590 : /*
1591 : * Don't know, must run full check.
1592 : */
1593 0 : break;
1594 :
1595 4 : case FKCONSTR_MATCH_FULL:
1596 :
1597 : /*
1598 : * If some new key values are NULL, the row fails the
1599 : * constraint. We must not throw error here, because the row
1600 : * might get invalidated before the constraint is to be
1601 : * checked, but we should queue the event to apply the check
1602 : * later.
1603 : */
1604 4 : return true;
1605 : }
1606 : }
1607 :
1608 : /*
1609 : * Continues here for no new key values are NULL, or we couldn't decide
1610 : * yet.
1611 : */
1612 :
1613 : /*
1614 : * If the original row was inserted by our own transaction, we must fire
1615 : * the trigger whether or not the keys are equal. This is because our
1616 : * UPDATE will invalidate the INSERT so that the INSERT RI trigger will
1617 : * not do anything; so we had better do the UPDATE check. (We could skip
1618 : * this if we knew the INSERT trigger already fired, but there is no easy
1619 : * way to know that.)
1620 : */
1621 564 : if (slot_is_current_xact_tuple(oldslot))
1622 77 : return true;
1623 :
1624 : /* If all old and new key values are equal, no check is needed */
1625 487 : if (ri_KeysEqual(fk_rel, oldslot, newslot, riinfo, false))
1626 262 : return false;
1627 :
1628 : /* Else we need to fire the trigger. */
1629 225 : return true;
1630 : }
1631 :
1632 : /*
1633 : * RI_Initial_Check -
1634 : *
1635 : * Check an entire table for non-matching values using a single query.
1636 : * This is not a trigger procedure, but is called during ALTER TABLE
1637 : * ADD FOREIGN KEY to validate the initial table contents.
1638 : *
1639 : * We expect that the caller has made provision to prevent any problems
1640 : * caused by concurrent actions. This could be either by locking rel and
1641 : * pkrel at ShareRowExclusiveLock or higher, or by otherwise ensuring
1642 : * that triggers implementing the checks are already active.
1643 : * Hence, we do not need to lock individual rows for the check.
1644 : *
1645 : * If the check fails because the current user doesn't have permissions
1646 : * to read both tables, return false to let our caller know that they will
1647 : * need to do something else to check the constraint.
1648 : */
1649 : bool
1650 765 : RI_Initial_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
1651 : {
1652 : const RI_ConstraintInfo *riinfo;
1653 : StringInfoData querybuf;
1654 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
1655 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1656 : char pkattname[MAX_QUOTED_NAME_LEN + 3];
1657 : char fkattname[MAX_QUOTED_NAME_LEN + 3];
1658 : RangeTblEntry *rte;
1659 : RTEPermissionInfo *pk_perminfo;
1660 : RTEPermissionInfo *fk_perminfo;
1661 765 : List *rtes = NIL;
1662 765 : List *perminfos = NIL;
1663 : const char *sep;
1664 : const char *fk_only;
1665 : const char *pk_only;
1666 : int save_nestlevel;
1667 : char workmembuf[32];
1668 : int spi_result;
1669 : SPIPlanPtr qplan;
1670 :
1671 765 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1672 :
1673 : /*
1674 : * Check to make sure current user has enough permissions to do the test
1675 : * query. (If not, caller can fall back to the trigger method, which
1676 : * works because it changes user IDs on the fly.)
1677 : *
1678 : * XXX are there any other show-stopper conditions to check?
1679 : */
1680 765 : pk_perminfo = makeNode(RTEPermissionInfo);
1681 765 : pk_perminfo->relid = RelationGetRelid(pk_rel);
1682 765 : pk_perminfo->requiredPerms = ACL_SELECT;
1683 765 : perminfos = lappend(perminfos, pk_perminfo);
1684 765 : rte = makeNode(RangeTblEntry);
1685 765 : rte->rtekind = RTE_RELATION;
1686 765 : rte->relid = RelationGetRelid(pk_rel);
1687 765 : rte->relkind = pk_rel->rd_rel->relkind;
1688 765 : rte->rellockmode = AccessShareLock;
1689 765 : rte->perminfoindex = list_length(perminfos);
1690 765 : rtes = lappend(rtes, rte);
1691 :
1692 765 : fk_perminfo = makeNode(RTEPermissionInfo);
1693 765 : fk_perminfo->relid = RelationGetRelid(fk_rel);
1694 765 : fk_perminfo->requiredPerms = ACL_SELECT;
1695 765 : perminfos = lappend(perminfos, fk_perminfo);
1696 765 : rte = makeNode(RangeTblEntry);
1697 765 : rte->rtekind = RTE_RELATION;
1698 765 : rte->relid = RelationGetRelid(fk_rel);
1699 765 : rte->relkind = fk_rel->rd_rel->relkind;
1700 765 : rte->rellockmode = AccessShareLock;
1701 765 : rte->perminfoindex = list_length(perminfos);
1702 765 : rtes = lappend(rtes, rte);
1703 :
1704 1799 : for (int i = 0; i < riinfo->nkeys; i++)
1705 : {
1706 : int attno;
1707 :
1708 1034 : attno = riinfo->pk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
1709 1034 : pk_perminfo->selectedCols = bms_add_member(pk_perminfo->selectedCols, attno);
1710 :
1711 1034 : attno = riinfo->fk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
1712 1034 : fk_perminfo->selectedCols = bms_add_member(fk_perminfo->selectedCols, attno);
1713 : }
1714 :
1715 765 : if (!ExecCheckPermissions(rtes, perminfos, false))
1716 8 : return false;
1717 :
1718 : /*
1719 : * Also punt if RLS is enabled on either table unless this role has the
1720 : * bypassrls right or is the table owner of the table(s) involved which
1721 : * have RLS enabled.
1722 : */
1723 757 : if (!has_bypassrls_privilege(GetUserId()) &&
1724 0 : ((pk_rel->rd_rel->relrowsecurity &&
1725 0 : !object_ownercheck(RelationRelationId, RelationGetRelid(pk_rel),
1726 0 : GetUserId())) ||
1727 0 : (fk_rel->rd_rel->relrowsecurity &&
1728 0 : !object_ownercheck(RelationRelationId, RelationGetRelid(fk_rel),
1729 : GetUserId()))))
1730 0 : return false;
1731 :
1732 : /*----------
1733 : * The query string built is:
1734 : * SELECT fk.keycols FROM [ONLY] relname fk
1735 : * LEFT OUTER JOIN [ONLY] pkrelname pk
1736 : * ON (pk.pkkeycol1=fk.keycol1 [AND ...])
1737 : * WHERE pk.pkkeycol1 IS NULL AND
1738 : * For MATCH SIMPLE:
1739 : * (fk.keycol1 IS NOT NULL [AND ...])
1740 : * For MATCH FULL:
1741 : * (fk.keycol1 IS NOT NULL [OR ...])
1742 : *
1743 : * We attach COLLATE clauses to the operators when comparing columns
1744 : * that have different collations.
1745 : *----------
1746 : */
1747 757 : initStringInfo(&querybuf);
1748 757 : appendStringInfoString(&querybuf, "SELECT ");
1749 757 : sep = "";
1750 1775 : for (int i = 0; i < riinfo->nkeys; i++)
1751 : {
1752 1018 : quoteOneName(fkattname,
1753 1018 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1754 1018 : appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
1755 1018 : sep = ", ";
1756 : }
1757 :
1758 757 : quoteRelationName(pkrelname, pk_rel);
1759 757 : quoteRelationName(fkrelname, fk_rel);
1760 1514 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1761 757 : "" : "ONLY ";
1762 1514 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1763 757 : "" : "ONLY ";
1764 757 : appendStringInfo(&querybuf,
1765 : " FROM %s%s fk LEFT OUTER JOIN %s%s pk ON",
1766 : fk_only, fkrelname, pk_only, pkrelname);
1767 :
1768 757 : strcpy(pkattname, "pk.");
1769 757 : strcpy(fkattname, "fk.");
1770 757 : sep = "(";
1771 1775 : for (int i = 0; i < riinfo->nkeys; i++)
1772 : {
1773 1018 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1774 1018 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1775 1018 : Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
1776 1018 : Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
1777 :
1778 1018 : quoteOneName(pkattname + 3,
1779 1018 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
1780 1018 : quoteOneName(fkattname + 3,
1781 1018 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1782 1018 : ri_GenerateQual(&querybuf, sep,
1783 : pkattname, pk_type,
1784 1018 : riinfo->pf_eq_oprs[i],
1785 : fkattname, fk_type);
1786 1018 : if (pk_coll != fk_coll)
1787 8 : ri_GenerateQualCollation(&querybuf, pk_coll);
1788 1018 : sep = "AND";
1789 : }
1790 :
1791 : /*
1792 : * It's sufficient to test any one pk attribute for null to detect a join
1793 : * failure.
1794 : */
1795 757 : quoteOneName(pkattname, RIAttName(pk_rel, riinfo->pk_attnums[0]));
1796 757 : appendStringInfo(&querybuf, ") WHERE pk.%s IS NULL AND (", pkattname);
1797 :
1798 757 : sep = "";
1799 1775 : for (int i = 0; i < riinfo->nkeys; i++)
1800 : {
1801 1018 : quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
1802 1018 : appendStringInfo(&querybuf,
1803 : "%sfk.%s IS NOT NULL",
1804 : sep, fkattname);
1805 1018 : switch (riinfo->confmatchtype)
1806 : {
1807 944 : case FKCONSTR_MATCH_SIMPLE:
1808 944 : sep = " AND ";
1809 944 : break;
1810 74 : case FKCONSTR_MATCH_FULL:
1811 74 : sep = " OR ";
1812 74 : break;
1813 : }
1814 : }
1815 757 : appendStringInfoChar(&querybuf, ')');
1816 :
1817 : /*
1818 : * Temporarily increase work_mem so that the check query can be executed
1819 : * more efficiently. It seems okay to do this because the query is simple
1820 : * enough to not use a multiple of work_mem, and one typically would not
1821 : * have many large foreign-key validations happening concurrently. So
1822 : * this seems to meet the criteria for being considered a "maintenance"
1823 : * operation, and accordingly we use maintenance_work_mem. However, we
1824 : * must also set hash_mem_multiplier to 1, since it is surely not okay to
1825 : * let that get applied to the maintenance_work_mem value.
1826 : *
1827 : * We use the equivalent of a function SET option to allow the setting to
1828 : * persist for exactly the duration of the check query. guc.c also takes
1829 : * care of undoing the setting on error.
1830 : */
1831 757 : save_nestlevel = NewGUCNestLevel();
1832 :
1833 757 : snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
1834 757 : (void) set_config_option("work_mem", workmembuf,
1835 : PGC_USERSET, PGC_S_SESSION,
1836 : GUC_ACTION_SAVE, true, 0, false);
1837 757 : (void) set_config_option("hash_mem_multiplier", "1",
1838 : PGC_USERSET, PGC_S_SESSION,
1839 : GUC_ACTION_SAVE, true, 0, false);
1840 :
1841 757 : SPI_connect();
1842 :
1843 : /*
1844 : * Generate the plan. We don't need to cache it, and there are no
1845 : * arguments to the plan.
1846 : */
1847 757 : qplan = SPI_prepare(querybuf.data, 0, NULL);
1848 :
1849 757 : if (qplan == NULL)
1850 0 : elog(ERROR, "SPI_prepare returned %s for %s",
1851 : SPI_result_code_string(SPI_result), querybuf.data);
1852 :
1853 : /*
1854 : * Run the plan. For safety we force a current snapshot to be used. (In
1855 : * transaction-snapshot mode, this arguably violates transaction isolation
1856 : * rules, but we really haven't got much choice.) We don't need to
1857 : * register the snapshot, because SPI_execute_snapshot will see to it. We
1858 : * need at most one tuple returned, so pass limit = 1.
1859 : */
1860 757 : spi_result = SPI_execute_snapshot(qplan,
1861 : NULL, NULL,
1862 : GetLatestSnapshot(),
1863 : InvalidSnapshot,
1864 : true, false, 1);
1865 :
1866 : /* Check result */
1867 757 : if (spi_result != SPI_OK_SELECT)
1868 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
1869 :
1870 : /* Did we find a tuple violating the constraint? */
1871 757 : if (SPI_processed > 0)
1872 : {
1873 : TupleTableSlot *slot;
1874 59 : HeapTuple tuple = SPI_tuptable->vals[0];
1875 59 : TupleDesc tupdesc = SPI_tuptable->tupdesc;
1876 : RI_ConstraintInfo fake_riinfo;
1877 :
1878 59 : slot = MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual);
1879 :
1880 59 : heap_deform_tuple(tuple, tupdesc,
1881 : slot->tts_values, slot->tts_isnull);
1882 59 : ExecStoreVirtualTuple(slot);
1883 :
1884 : /*
1885 : * The columns to look at in the result tuple are 1..N, not whatever
1886 : * they are in the fk_rel. Hack up riinfo so that the subroutines
1887 : * called here will behave properly.
1888 : *
1889 : * In addition to this, we have to pass the correct tupdesc to
1890 : * ri_ReportViolation, overriding its normal habit of using the pk_rel
1891 : * or fk_rel's tupdesc.
1892 : */
1893 59 : memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
1894 134 : for (int i = 0; i < fake_riinfo.nkeys; i++)
1895 75 : fake_riinfo.fk_attnums[i] = i + 1;
1896 :
1897 : /*
1898 : * If it's MATCH FULL, and there are any nulls in the FK keys,
1899 : * complain about that rather than the lack of a match. MATCH FULL
1900 : * disallows partially-null FK rows.
1901 : */
1902 79 : if (fake_riinfo.confmatchtype == FKCONSTR_MATCH_FULL &&
1903 20 : ri_NullCheck(tupdesc, slot, &fake_riinfo, false) != RI_KEYS_NONE_NULL)
1904 8 : ereport(ERROR,
1905 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
1906 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
1907 : RelationGetRelationName(fk_rel),
1908 : NameStr(fake_riinfo.conname)),
1909 : errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
1910 : errtableconstraint(fk_rel,
1911 : NameStr(fake_riinfo.conname))));
1912 :
1913 : /*
1914 : * We tell ri_ReportViolation we were doing the RI_PLAN_CHECK_LOOKUPPK
1915 : * query, which isn't true, but will cause it to use
1916 : * fake_riinfo.fk_attnums as we need.
1917 : */
1918 51 : ri_ReportViolation(&fake_riinfo,
1919 : pk_rel, fk_rel,
1920 : slot, tupdesc,
1921 : RI_PLAN_CHECK_LOOKUPPK, false, false);
1922 :
1923 : ExecDropSingleTupleTableSlot(slot);
1924 : }
1925 :
1926 698 : if (SPI_finish() != SPI_OK_FINISH)
1927 0 : elog(ERROR, "SPI_finish failed");
1928 :
1929 : /*
1930 : * Restore work_mem and hash_mem_multiplier.
1931 : */
1932 698 : AtEOXact_GUC(true, save_nestlevel);
1933 :
1934 698 : return true;
1935 : }
1936 :
1937 : /*
1938 : * RI_PartitionRemove_Check -
1939 : *
1940 : * Verify no referencing values exist, when a partition is detached on
1941 : * the referenced side of a foreign key constraint.
1942 : */
1943 : void
1944 65 : RI_PartitionRemove_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
1945 : {
1946 : const RI_ConstraintInfo *riinfo;
1947 : StringInfoData querybuf;
1948 : char *constraintDef;
1949 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
1950 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1951 : char pkattname[MAX_QUOTED_NAME_LEN + 3];
1952 : char fkattname[MAX_QUOTED_NAME_LEN + 3];
1953 : const char *sep;
1954 : const char *fk_only;
1955 : int save_nestlevel;
1956 : char workmembuf[32];
1957 : int spi_result;
1958 : SPIPlanPtr qplan;
1959 : int i;
1960 :
1961 65 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1962 :
1963 : /*
1964 : * We don't check permissions before displaying the error message, on the
1965 : * assumption that the user detaching the partition must have enough
1966 : * privileges to examine the table contents anyhow.
1967 : */
1968 :
1969 : /*----------
1970 : * The query string built is:
1971 : * SELECT fk.keycols FROM [ONLY] relname fk
1972 : * JOIN pkrelname pk
1973 : * ON (pk.pkkeycol1=fk.keycol1 [AND ...])
1974 : * WHERE (<partition constraint>) AND
1975 : * For MATCH SIMPLE:
1976 : * (fk.keycol1 IS NOT NULL [AND ...])
1977 : * For MATCH FULL:
1978 : * (fk.keycol1 IS NOT NULL [OR ...])
1979 : *
1980 : * We attach COLLATE clauses to the operators when comparing columns
1981 : * that have different collations.
1982 : *----------
1983 : */
1984 65 : initStringInfo(&querybuf);
1985 65 : appendStringInfoString(&querybuf, "SELECT ");
1986 65 : sep = "";
1987 130 : for (i = 0; i < riinfo->nkeys; i++)
1988 : {
1989 65 : quoteOneName(fkattname,
1990 65 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1991 65 : appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
1992 65 : sep = ", ";
1993 : }
1994 :
1995 65 : quoteRelationName(pkrelname, pk_rel);
1996 65 : quoteRelationName(fkrelname, fk_rel);
1997 130 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1998 65 : "" : "ONLY ";
1999 65 : appendStringInfo(&querybuf,
2000 : " FROM %s%s fk JOIN %s pk ON",
2001 : fk_only, fkrelname, pkrelname);
2002 65 : strcpy(pkattname, "pk.");
2003 65 : strcpy(fkattname, "fk.");
2004 65 : sep = "(";
2005 130 : for (i = 0; i < riinfo->nkeys; i++)
2006 : {
2007 65 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
2008 65 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
2009 65 : Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
2010 65 : Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
2011 :
2012 65 : quoteOneName(pkattname + 3,
2013 65 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
2014 65 : quoteOneName(fkattname + 3,
2015 65 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
2016 65 : ri_GenerateQual(&querybuf, sep,
2017 : pkattname, pk_type,
2018 65 : riinfo->pf_eq_oprs[i],
2019 : fkattname, fk_type);
2020 65 : if (pk_coll != fk_coll)
2021 0 : ri_GenerateQualCollation(&querybuf, pk_coll);
2022 65 : sep = "AND";
2023 : }
2024 :
2025 : /*
2026 : * Start the WHERE clause with the partition constraint (except if this is
2027 : * the default partition and there's no other partition, because the
2028 : * partition constraint is the empty string in that case.)
2029 : */
2030 65 : constraintDef = pg_get_partconstrdef_string(RelationGetRelid(pk_rel), "pk");
2031 65 : if (constraintDef && constraintDef[0] != '\0')
2032 65 : appendStringInfo(&querybuf, ") WHERE %s AND (",
2033 : constraintDef);
2034 : else
2035 0 : appendStringInfoString(&querybuf, ") WHERE (");
2036 :
2037 65 : sep = "";
2038 130 : for (i = 0; i < riinfo->nkeys; i++)
2039 : {
2040 65 : quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
2041 65 : appendStringInfo(&querybuf,
2042 : "%sfk.%s IS NOT NULL",
2043 : sep, fkattname);
2044 65 : switch (riinfo->confmatchtype)
2045 : {
2046 65 : case FKCONSTR_MATCH_SIMPLE:
2047 65 : sep = " AND ";
2048 65 : break;
2049 0 : case FKCONSTR_MATCH_FULL:
2050 0 : sep = " OR ";
2051 0 : break;
2052 : }
2053 : }
2054 65 : appendStringInfoChar(&querybuf, ')');
2055 :
2056 : /*
2057 : * Temporarily increase work_mem so that the check query can be executed
2058 : * more efficiently. It seems okay to do this because the query is simple
2059 : * enough to not use a multiple of work_mem, and one typically would not
2060 : * have many large foreign-key validations happening concurrently. So
2061 : * this seems to meet the criteria for being considered a "maintenance"
2062 : * operation, and accordingly we use maintenance_work_mem. However, we
2063 : * must also set hash_mem_multiplier to 1, since it is surely not okay to
2064 : * let that get applied to the maintenance_work_mem value.
2065 : *
2066 : * We use the equivalent of a function SET option to allow the setting to
2067 : * persist for exactly the duration of the check query. guc.c also takes
2068 : * care of undoing the setting on error.
2069 : */
2070 65 : save_nestlevel = NewGUCNestLevel();
2071 :
2072 65 : snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
2073 65 : (void) set_config_option("work_mem", workmembuf,
2074 : PGC_USERSET, PGC_S_SESSION,
2075 : GUC_ACTION_SAVE, true, 0, false);
2076 65 : (void) set_config_option("hash_mem_multiplier", "1",
2077 : PGC_USERSET, PGC_S_SESSION,
2078 : GUC_ACTION_SAVE, true, 0, false);
2079 :
2080 65 : SPI_connect();
2081 :
2082 : /*
2083 : * Generate the plan. We don't need to cache it, and there are no
2084 : * arguments to the plan.
2085 : */
2086 65 : qplan = SPI_prepare(querybuf.data, 0, NULL);
2087 :
2088 65 : if (qplan == NULL)
2089 0 : elog(ERROR, "SPI_prepare returned %s for %s",
2090 : SPI_result_code_string(SPI_result), querybuf.data);
2091 :
2092 : /*
2093 : * Run the plan. For safety we force a current snapshot to be used. (In
2094 : * transaction-snapshot mode, this arguably violates transaction isolation
2095 : * rules, but we really haven't got much choice.) We don't need to
2096 : * register the snapshot, because SPI_execute_snapshot will see to it. We
2097 : * need at most one tuple returned, so pass limit = 1.
2098 : */
2099 65 : spi_result = SPI_execute_snapshot(qplan,
2100 : NULL, NULL,
2101 : GetLatestSnapshot(),
2102 : InvalidSnapshot,
2103 : true, false, 1);
2104 :
2105 : /* Check result */
2106 65 : if (spi_result != SPI_OK_SELECT)
2107 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
2108 :
2109 : /* Did we find a tuple that would violate the constraint? */
2110 65 : if (SPI_processed > 0)
2111 : {
2112 : TupleTableSlot *slot;
2113 22 : HeapTuple tuple = SPI_tuptable->vals[0];
2114 22 : TupleDesc tupdesc = SPI_tuptable->tupdesc;
2115 : RI_ConstraintInfo fake_riinfo;
2116 :
2117 22 : slot = MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual);
2118 :
2119 22 : heap_deform_tuple(tuple, tupdesc,
2120 : slot->tts_values, slot->tts_isnull);
2121 22 : ExecStoreVirtualTuple(slot);
2122 :
2123 : /*
2124 : * The columns to look at in the result tuple are 1..N, not whatever
2125 : * they are in the fk_rel. Hack up riinfo so that ri_ReportViolation
2126 : * will behave properly.
2127 : *
2128 : * In addition to this, we have to pass the correct tupdesc to
2129 : * ri_ReportViolation, overriding its normal habit of using the pk_rel
2130 : * or fk_rel's tupdesc.
2131 : */
2132 22 : memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
2133 44 : for (i = 0; i < fake_riinfo.nkeys; i++)
2134 22 : fake_riinfo.pk_attnums[i] = i + 1;
2135 :
2136 22 : ri_ReportViolation(&fake_riinfo, pk_rel, fk_rel,
2137 : slot, tupdesc, 0, false, true);
2138 : }
2139 :
2140 43 : if (SPI_finish() != SPI_OK_FINISH)
2141 0 : elog(ERROR, "SPI_finish failed");
2142 :
2143 : /*
2144 : * Restore work_mem and hash_mem_multiplier.
2145 : */
2146 43 : AtEOXact_GUC(true, save_nestlevel);
2147 43 : }
2148 :
2149 :
2150 : /* ----------
2151 : * Local functions below
2152 : * ----------
2153 : */
2154 :
2155 :
2156 : /*
2157 : * quoteOneName --- safely quote a single SQL name
2158 : *
2159 : * buffer must be MAX_QUOTED_NAME_LEN long (includes room for \0)
2160 : */
2161 : static void
2162 13195 : quoteOneName(char *buffer, const char *name)
2163 : {
2164 : /* Rather than trying to be smart, just always quote it. */
2165 13195 : *buffer++ = '"';
2166 81509 : while (*name)
2167 : {
2168 68314 : if (*name == '"')
2169 0 : *buffer++ = '"';
2170 68314 : *buffer++ = *name++;
2171 : }
2172 13195 : *buffer++ = '"';
2173 13195 : *buffer = '\0';
2174 13195 : }
2175 :
2176 : /*
2177 : * quoteRelationName --- safely quote a fully qualified relation name
2178 : *
2179 : * buffer must be MAX_QUOTED_REL_NAME_LEN long (includes room for \0)
2180 : */
2181 : static void
2182 2923 : quoteRelationName(char *buffer, Relation rel)
2183 : {
2184 2923 : quoteOneName(buffer, get_namespace_name(RelationGetNamespace(rel)));
2185 2923 : buffer += strlen(buffer);
2186 2923 : *buffer++ = '.';
2187 2923 : quoteOneName(buffer, RelationGetRelationName(rel));
2188 2923 : }
2189 :
2190 : /*
2191 : * ri_GenerateQual --- generate a WHERE clause equating two variables
2192 : *
2193 : * This basically appends " sep leftop op rightop" to buf, adding casts
2194 : * and schema qualification as needed to ensure that the parser will select
2195 : * the operator we specify. leftop and rightop should be parenthesized
2196 : * if they aren't variables or parameters.
2197 : */
2198 : static void
2199 3157 : ri_GenerateQual(StringInfo buf,
2200 : const char *sep,
2201 : const char *leftop, Oid leftoptype,
2202 : Oid opoid,
2203 : const char *rightop, Oid rightoptype)
2204 : {
2205 3157 : appendStringInfo(buf, " %s ", sep);
2206 3157 : generate_operator_clause(buf, leftop, leftoptype, opoid,
2207 : rightop, rightoptype);
2208 3157 : }
2209 :
2210 : /*
2211 : * ri_GenerateQualCollation --- add a COLLATE spec to a WHERE clause
2212 : *
2213 : * We only have to use this function when directly comparing the referencing
2214 : * and referenced columns, if they are of different collations; else the
2215 : * parser will fail to resolve the collation to use. We don't need to use
2216 : * this function for RI queries that compare a variable to a $n parameter.
2217 : * Since parameter symbols always have default collation, the effect will be
2218 : * to use the variable's collation.
2219 : *
2220 : * Note that we require that the collations of the referencing and the
2221 : * referenced column have the same notion of equality: Either they have to
2222 : * both be deterministic or else they both have to be the same. (See also
2223 : * ATAddForeignKeyConstraint().)
2224 : */
2225 : static void
2226 8 : ri_GenerateQualCollation(StringInfo buf, Oid collation)
2227 : {
2228 : HeapTuple tp;
2229 : Form_pg_collation colltup;
2230 : char *collname;
2231 : char onename[MAX_QUOTED_NAME_LEN];
2232 :
2233 : /* Nothing to do if it's a noncollatable data type */
2234 8 : if (!OidIsValid(collation))
2235 0 : return;
2236 :
2237 8 : tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(collation));
2238 8 : if (!HeapTupleIsValid(tp))
2239 0 : elog(ERROR, "cache lookup failed for collation %u", collation);
2240 8 : colltup = (Form_pg_collation) GETSTRUCT(tp);
2241 8 : collname = NameStr(colltup->collname);
2242 :
2243 : /*
2244 : * We qualify the name always, for simplicity and to ensure the query is
2245 : * not search-path-dependent.
2246 : */
2247 8 : quoteOneName(onename, get_namespace_name(colltup->collnamespace));
2248 8 : appendStringInfo(buf, " COLLATE %s", onename);
2249 8 : quoteOneName(onename, collname);
2250 8 : appendStringInfo(buf, ".%s", onename);
2251 :
2252 8 : ReleaseSysCache(tp);
2253 : }
2254 :
2255 : /* ----------
2256 : * ri_BuildQueryKey -
2257 : *
2258 : * Construct a hashtable key for a prepared SPI plan of an FK constraint.
2259 : *
2260 : * key: output argument, *key is filled in based on the other arguments
2261 : * riinfo: info derived from pg_constraint entry
2262 : * constr_queryno: an internal number identifying the query type
2263 : * (see RI_PLAN_XXX constants at head of file)
2264 : * ----------
2265 : */
2266 : static void
2267 2475 : ri_BuildQueryKey(RI_QueryKey *key, const RI_ConstraintInfo *riinfo,
2268 : int32 constr_queryno)
2269 : {
2270 : /*
2271 : * Inherited constraints with a common ancestor can share ri_query_cache
2272 : * entries for all query types except RI_PLAN_CHECK_LOOKUPPK_FROM_PK.
2273 : * Except in that case, the query processes the other table involved in
2274 : * the FK constraint (i.e., not the table on which the trigger has been
2275 : * fired), and so it will be the same for all members of the inheritance
2276 : * tree. So we may use the root constraint's OID in the hash key, rather
2277 : * than the constraint's own OID. This avoids creating duplicate SPI
2278 : * plans, saving lots of work and memory when there are many partitions
2279 : * with similar FK constraints.
2280 : *
2281 : * (Note that we must still have a separate RI_ConstraintInfo for each
2282 : * constraint, because partitions can have different column orders,
2283 : * resulting in different pk_attnums[] or fk_attnums[] array contents.)
2284 : *
2285 : * We assume struct RI_QueryKey contains no padding bytes, else we'd need
2286 : * to use memset to clear them.
2287 : */
2288 2475 : if (constr_queryno != RI_PLAN_CHECK_LOOKUPPK_FROM_PK)
2289 1952 : key->constr_id = riinfo->constraint_root_id;
2290 : else
2291 523 : key->constr_id = riinfo->constraint_id;
2292 2475 : key->constr_queryno = constr_queryno;
2293 2475 : }
2294 :
2295 : /*
2296 : * Check that RI trigger function was called in expected context
2297 : */
2298 : static void
2299 605839 : ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname, int tgkind)
2300 : {
2301 605839 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
2302 :
2303 605839 : if (!CALLED_AS_TRIGGER(fcinfo))
2304 0 : ereport(ERROR,
2305 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2306 : errmsg("function \"%s\" was not called by trigger manager", funcname)));
2307 :
2308 : /*
2309 : * Check proper event
2310 : */
2311 605839 : if (!TRIGGER_FIRED_AFTER(trigdata->tg_event) ||
2312 605839 : !TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
2313 0 : ereport(ERROR,
2314 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2315 : errmsg("function \"%s\" must be fired AFTER ROW", funcname)));
2316 :
2317 605839 : switch (tgkind)
2318 : {
2319 604433 : case RI_TRIGTYPE_INSERT:
2320 604433 : if (!TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
2321 0 : ereport(ERROR,
2322 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2323 : errmsg("function \"%s\" must be fired for INSERT", funcname)));
2324 604433 : break;
2325 866 : case RI_TRIGTYPE_UPDATE:
2326 866 : if (!TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
2327 0 : ereport(ERROR,
2328 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2329 : errmsg("function \"%s\" must be fired for UPDATE", funcname)));
2330 866 : break;
2331 540 : case RI_TRIGTYPE_DELETE:
2332 540 : if (!TRIGGER_FIRED_BY_DELETE(trigdata->tg_event))
2333 0 : ereport(ERROR,
2334 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2335 : errmsg("function \"%s\" must be fired for DELETE", funcname)));
2336 540 : break;
2337 : }
2338 605839 : }
2339 :
2340 :
2341 : /*
2342 : * Fetch the RI_ConstraintInfo struct for the trigger's FK constraint.
2343 : */
2344 : static RI_ConstraintInfo *
2345 608958 : ri_FetchConstraintInfo(Trigger *trigger, Relation trig_rel, bool rel_is_pk)
2346 : {
2347 608958 : Oid constraintOid = trigger->tgconstraint;
2348 : RI_ConstraintInfo *riinfo;
2349 :
2350 : /*
2351 : * Check that the FK constraint's OID is available; it might not be if
2352 : * we've been invoked via an ordinary trigger or an old-style "constraint
2353 : * trigger".
2354 : */
2355 608958 : if (!OidIsValid(constraintOid))
2356 0 : ereport(ERROR,
2357 : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2358 : errmsg("no pg_constraint entry for trigger \"%s\" on table \"%s\"",
2359 : trigger->tgname, RelationGetRelationName(trig_rel)),
2360 : errhint("Remove this referential integrity trigger and its mates, then do ALTER TABLE ADD CONSTRAINT.")));
2361 :
2362 : /* Find or create a hashtable entry for the constraint */
2363 608958 : riinfo = ri_LoadConstraintInfo(constraintOid);
2364 :
2365 : /* Do some easy cross-checks against the trigger call data */
2366 608958 : if (rel_is_pk)
2367 : {
2368 2733 : if (riinfo->fk_relid != trigger->tgconstrrelid ||
2369 2733 : riinfo->pk_relid != RelationGetRelid(trig_rel))
2370 0 : elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
2371 : trigger->tgname, RelationGetRelationName(trig_rel));
2372 : }
2373 : else
2374 : {
2375 606225 : if (riinfo->fk_relid != RelationGetRelid(trig_rel) ||
2376 606225 : riinfo->pk_relid != trigger->tgconstrrelid)
2377 0 : elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
2378 : trigger->tgname, RelationGetRelationName(trig_rel));
2379 : }
2380 :
2381 608958 : if (riinfo->confmatchtype != FKCONSTR_MATCH_FULL &&
2382 608645 : riinfo->confmatchtype != FKCONSTR_MATCH_PARTIAL &&
2383 608645 : riinfo->confmatchtype != FKCONSTR_MATCH_SIMPLE)
2384 0 : elog(ERROR, "unrecognized confmatchtype: %d",
2385 : riinfo->confmatchtype);
2386 :
2387 608958 : if (riinfo->confmatchtype == FKCONSTR_MATCH_PARTIAL)
2388 0 : ereport(ERROR,
2389 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2390 : errmsg("MATCH PARTIAL not yet implemented")));
2391 :
2392 608958 : return riinfo;
2393 : }
2394 :
2395 : /*
2396 : * Fetch or create the RI_ConstraintInfo struct for an FK constraint.
2397 : */
2398 : static RI_ConstraintInfo *
2399 611624 : ri_LoadConstraintInfo(Oid constraintOid)
2400 : {
2401 : RI_ConstraintInfo *riinfo;
2402 : bool found;
2403 : HeapTuple tup;
2404 : Form_pg_constraint conForm;
2405 :
2406 : /*
2407 : * On the first call initialize the hashtable
2408 : */
2409 611624 : if (!ri_constraint_cache)
2410 264 : ri_InitHashTables();
2411 :
2412 : /*
2413 : * Find or create a hash entry. If we find a valid one, just return it.
2414 : */
2415 611624 : riinfo = (RI_ConstraintInfo *) hash_search(ri_constraint_cache,
2416 : &constraintOid,
2417 : HASH_ENTER, &found);
2418 611624 : if (!found)
2419 2482 : riinfo->valid = false;
2420 609142 : else if (riinfo->valid)
2421 608878 : return riinfo;
2422 :
2423 : /*
2424 : * Fetch the pg_constraint row so we can fill in the entry.
2425 : */
2426 2746 : tup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constraintOid));
2427 2746 : if (!HeapTupleIsValid(tup)) /* should not happen */
2428 0 : elog(ERROR, "cache lookup failed for constraint %u", constraintOid);
2429 2746 : conForm = (Form_pg_constraint) GETSTRUCT(tup);
2430 :
2431 2746 : if (conForm->contype != CONSTRAINT_FOREIGN) /* should not happen */
2432 0 : elog(ERROR, "constraint %u is not a foreign key constraint",
2433 : constraintOid);
2434 :
2435 : /* And extract data */
2436 : Assert(riinfo->constraint_id == constraintOid);
2437 2746 : if (OidIsValid(conForm->conparentid))
2438 964 : riinfo->constraint_root_id =
2439 964 : get_ri_constraint_root(conForm->conparentid);
2440 : else
2441 1782 : riinfo->constraint_root_id = constraintOid;
2442 2746 : riinfo->oidHashValue = GetSysCacheHashValue1(CONSTROID,
2443 : ObjectIdGetDatum(constraintOid));
2444 2746 : riinfo->rootHashValue = GetSysCacheHashValue1(CONSTROID,
2445 : ObjectIdGetDatum(riinfo->constraint_root_id));
2446 2746 : memcpy(&riinfo->conname, &conForm->conname, sizeof(NameData));
2447 2746 : riinfo->pk_relid = conForm->confrelid;
2448 2746 : riinfo->fk_relid = conForm->conrelid;
2449 2746 : riinfo->confupdtype = conForm->confupdtype;
2450 2746 : riinfo->confdeltype = conForm->confdeltype;
2451 2746 : riinfo->confmatchtype = conForm->confmatchtype;
2452 2746 : riinfo->hasperiod = conForm->conperiod;
2453 :
2454 2746 : DeconstructFkConstraintRow(tup,
2455 : &riinfo->nkeys,
2456 2746 : riinfo->fk_attnums,
2457 2746 : riinfo->pk_attnums,
2458 2746 : riinfo->pf_eq_oprs,
2459 2746 : riinfo->pp_eq_oprs,
2460 2746 : riinfo->ff_eq_oprs,
2461 : &riinfo->ndelsetcols,
2462 2746 : riinfo->confdelsetcols);
2463 :
2464 : /*
2465 : * For temporal FKs, get the operators and functions we need. We ask the
2466 : * opclass of the PK element for these. This all gets cached (as does the
2467 : * generated plan), so there's no performance issue.
2468 : */
2469 2746 : if (riinfo->hasperiod)
2470 : {
2471 141 : Oid opclass = get_index_column_opclass(conForm->conindid, riinfo->nkeys);
2472 :
2473 141 : FindFKPeriodOpers(opclass,
2474 : &riinfo->period_contained_by_oper,
2475 : &riinfo->agged_period_contained_by_oper,
2476 : &riinfo->period_intersect_oper);
2477 : }
2478 :
2479 : /* Metadata used by fast path. */
2480 2746 : riinfo->conindid = conForm->conindid;
2481 2746 : riinfo->pk_is_partitioned =
2482 2746 : (get_rel_relkind(riinfo->pk_relid) == RELKIND_PARTITIONED_TABLE);
2483 :
2484 2746 : ReleaseSysCache(tup);
2485 :
2486 : /*
2487 : * For efficient processing of invalidation messages below, we keep a
2488 : * doubly-linked count list of all currently valid entries.
2489 : */
2490 2746 : dclist_push_tail(&ri_constraint_cache_valid_list, &riinfo->valid_link);
2491 :
2492 2746 : riinfo->valid = true;
2493 :
2494 2746 : riinfo->fpmeta = NULL;
2495 :
2496 2746 : return riinfo;
2497 : }
2498 :
2499 : /*
2500 : * get_ri_constraint_root
2501 : * Returns the OID of the constraint's root parent
2502 : */
2503 : static Oid
2504 964 : get_ri_constraint_root(Oid constrOid)
2505 : {
2506 : for (;;)
2507 232 : {
2508 : HeapTuple tuple;
2509 : Oid constrParentOid;
2510 :
2511 1196 : tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constrOid));
2512 1196 : if (!HeapTupleIsValid(tuple))
2513 0 : elog(ERROR, "cache lookup failed for constraint %u", constrOid);
2514 1196 : constrParentOid = ((Form_pg_constraint) GETSTRUCT(tuple))->conparentid;
2515 1196 : ReleaseSysCache(tuple);
2516 1196 : if (!OidIsValid(constrParentOid))
2517 964 : break; /* we reached the root constraint */
2518 232 : constrOid = constrParentOid;
2519 : }
2520 964 : return constrOid;
2521 : }
2522 :
2523 : /*
2524 : * Callback for pg_constraint inval events
2525 : *
2526 : * While most syscache callbacks just flush all their entries, pg_constraint
2527 : * gets enough update traffic that it's probably worth being smarter.
2528 : * Invalidate any ri_constraint_cache entry associated with the syscache
2529 : * entry with the specified hash value, or all entries if hashvalue == 0.
2530 : *
2531 : * Note: at the time a cache invalidation message is processed there may be
2532 : * active references to the cache. Because of this we never remove entries
2533 : * from the cache, but only mark them invalid, which is harmless to active
2534 : * uses. (Any query using an entry should hold a lock sufficient to keep that
2535 : * data from changing under it --- but we may get cache flushes anyway.)
2536 : */
2537 : static void
2538 57437 : InvalidateConstraintCacheCallBack(Datum arg, SysCacheIdentifier cacheid,
2539 : uint32 hashvalue)
2540 : {
2541 : dlist_mutable_iter iter;
2542 :
2543 : Assert(ri_constraint_cache != NULL);
2544 :
2545 : /*
2546 : * If the list of currently valid entries gets excessively large, we mark
2547 : * them all invalid so we can empty the list. This arrangement avoids
2548 : * O(N^2) behavior in situations where a session touches many foreign keys
2549 : * and also does many ALTER TABLEs, such as a restore from pg_dump.
2550 : */
2551 57437 : if (dclist_count(&ri_constraint_cache_valid_list) > 1000)
2552 0 : hashvalue = 0; /* pretend it's a cache reset */
2553 :
2554 243344 : dclist_foreach_modify(iter, &ri_constraint_cache_valid_list)
2555 : {
2556 185907 : RI_ConstraintInfo *riinfo = dclist_container(RI_ConstraintInfo,
2557 : valid_link, iter.cur);
2558 :
2559 : /*
2560 : * We must invalidate not only entries directly matching the given
2561 : * hash value, but also child entries, in case the invalidation
2562 : * affects a root constraint.
2563 : */
2564 185907 : if (hashvalue == 0 ||
2565 185864 : riinfo->oidHashValue == hashvalue ||
2566 184134 : riinfo->rootHashValue == hashvalue)
2567 : {
2568 1989 : riinfo->valid = false;
2569 1989 : if (riinfo->fpmeta)
2570 : {
2571 648 : pfree(riinfo->fpmeta);
2572 648 : riinfo->fpmeta = NULL;
2573 : }
2574 : /* Remove invalidated entries from the list, too */
2575 1989 : dclist_delete_from(&ri_constraint_cache_valid_list, iter.cur);
2576 : }
2577 : }
2578 57437 : }
2579 :
2580 :
2581 : /*
2582 : * Prepare execution plan for a query to enforce an RI restriction
2583 : */
2584 : static SPIPlanPtr
2585 1188 : ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
2586 : RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel)
2587 : {
2588 : SPIPlanPtr qplan;
2589 : Relation query_rel;
2590 : Oid save_userid;
2591 : int save_sec_context;
2592 :
2593 : /*
2594 : * Use the query type code to determine whether the query is run against
2595 : * the PK or FK table; we'll do the check as that table's owner
2596 : */
2597 1188 : if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
2598 624 : query_rel = pk_rel;
2599 : else
2600 564 : query_rel = fk_rel;
2601 :
2602 : /* Switch to proper UID to perform check as */
2603 1188 : GetUserIdAndSecContext(&save_userid, &save_sec_context);
2604 1188 : SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
2605 : save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
2606 : SECURITY_NOFORCE_RLS);
2607 :
2608 : /* Create the plan */
2609 1188 : qplan = SPI_prepare(querystr, nargs, argtypes);
2610 :
2611 1188 : if (qplan == NULL)
2612 0 : elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), querystr);
2613 :
2614 : /* Restore UID and security context */
2615 1188 : SetUserIdAndSecContext(save_userid, save_sec_context);
2616 :
2617 : /* Save the plan */
2618 1188 : SPI_keepplan(qplan);
2619 1188 : ri_HashPreparedPlan(qkey, qplan);
2620 :
2621 1188 : return qplan;
2622 : }
2623 :
2624 : /*
2625 : * Perform a query to enforce an RI restriction
2626 : */
2627 : static bool
2628 2475 : ri_PerformCheck(const RI_ConstraintInfo *riinfo,
2629 : RI_QueryKey *qkey, SPIPlanPtr qplan,
2630 : Relation fk_rel, Relation pk_rel,
2631 : TupleTableSlot *oldslot, TupleTableSlot *newslot,
2632 : bool is_restrict,
2633 : bool detectNewRows, int expect_OK)
2634 : {
2635 : Relation query_rel,
2636 : source_rel;
2637 : bool source_is_pk;
2638 : Snapshot test_snapshot;
2639 : Snapshot crosscheck_snapshot;
2640 : int limit;
2641 : int spi_result;
2642 : Oid save_userid;
2643 : int save_sec_context;
2644 : Datum vals[RI_MAX_NUMKEYS * 2];
2645 : char nulls[RI_MAX_NUMKEYS * 2];
2646 :
2647 : /*
2648 : * Use the query type code to determine whether the query is run against
2649 : * the PK or FK table; we'll do the check as that table's owner
2650 : */
2651 2475 : if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
2652 1313 : query_rel = pk_rel;
2653 : else
2654 1162 : query_rel = fk_rel;
2655 :
2656 : /*
2657 : * The values for the query are taken from the table on which the trigger
2658 : * is called - it is normally the other one with respect to query_rel. An
2659 : * exception is ri_Check_Pk_Match(), which uses the PK table for both (and
2660 : * sets queryno to RI_PLAN_CHECK_LOOKUPPK_FROM_PK). We might eventually
2661 : * need some less klugy way to determine this.
2662 : */
2663 2475 : if (qkey->constr_queryno == RI_PLAN_CHECK_LOOKUPPK)
2664 : {
2665 790 : source_rel = fk_rel;
2666 790 : source_is_pk = false;
2667 : }
2668 : else
2669 : {
2670 1685 : source_rel = pk_rel;
2671 1685 : source_is_pk = true;
2672 : }
2673 :
2674 : /* Extract the parameters to be passed into the query */
2675 2475 : if (newslot)
2676 : {
2677 934 : ri_ExtractValues(source_rel, newslot, riinfo, source_is_pk,
2678 : vals, nulls);
2679 934 : if (oldslot)
2680 144 : ri_ExtractValues(source_rel, oldslot, riinfo, source_is_pk,
2681 144 : vals + riinfo->nkeys, nulls + riinfo->nkeys);
2682 : }
2683 : else
2684 : {
2685 1541 : ri_ExtractValues(source_rel, oldslot, riinfo, source_is_pk,
2686 : vals, nulls);
2687 : }
2688 :
2689 : /*
2690 : * In READ COMMITTED mode, we just need to use an up-to-date regular
2691 : * snapshot, and we will see all rows that could be interesting. But in
2692 : * transaction-snapshot mode, we can't change the transaction snapshot. If
2693 : * the caller passes detectNewRows == false then it's okay to do the query
2694 : * with the transaction snapshot; otherwise we use a current snapshot, and
2695 : * tell the executor to error out if it finds any rows under the current
2696 : * snapshot that wouldn't be visible per the transaction snapshot. Note
2697 : * that SPI_execute_snapshot will register the snapshots, so we don't need
2698 : * to bother here.
2699 : */
2700 2475 : if (IsolationUsesXactSnapshot() && detectNewRows)
2701 : {
2702 36 : CommandCounterIncrement(); /* be sure all my own work is visible */
2703 36 : test_snapshot = GetLatestSnapshot();
2704 36 : crosscheck_snapshot = GetTransactionSnapshot();
2705 : }
2706 : else
2707 : {
2708 : /* the default SPI behavior is okay */
2709 2439 : test_snapshot = InvalidSnapshot;
2710 2439 : crosscheck_snapshot = InvalidSnapshot;
2711 : }
2712 :
2713 : /*
2714 : * If this is a select query (e.g., for a 'no action' or 'restrict'
2715 : * trigger), we only need to see if there is a single row in the table,
2716 : * matching the key. Otherwise, limit = 0 - because we want the query to
2717 : * affect ALL the matching rows.
2718 : */
2719 2475 : limit = (expect_OK == SPI_OK_SELECT) ? 1 : 0;
2720 :
2721 : /* Switch to proper UID to perform check as */
2722 2475 : GetUserIdAndSecContext(&save_userid, &save_sec_context);
2723 2475 : SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
2724 : save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
2725 : SECURITY_NOFORCE_RLS);
2726 :
2727 : /*
2728 : * Finally we can run the query.
2729 : *
2730 : * Set fire_triggers to false to ensure that AFTER triggers are queued in
2731 : * the outer query's after-trigger context and fire after all RI updates
2732 : * on the same row are complete, rather than immediately.
2733 : */
2734 2475 : spi_result = SPI_execute_snapshot(qplan,
2735 : vals, nulls,
2736 : test_snapshot, crosscheck_snapshot,
2737 : false, false, limit);
2738 :
2739 : /* Restore UID and security context */
2740 2465 : SetUserIdAndSecContext(save_userid, save_sec_context);
2741 :
2742 : /* Check result */
2743 2465 : if (spi_result < 0)
2744 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
2745 :
2746 2465 : if (expect_OK >= 0 && spi_result != expect_OK)
2747 0 : ereport(ERROR,
2748 : (errcode(ERRCODE_INTERNAL_ERROR),
2749 : errmsg("referential integrity query on \"%s\" from constraint \"%s\" on \"%s\" gave unexpected result",
2750 : RelationGetRelationName(pk_rel),
2751 : NameStr(riinfo->conname),
2752 : RelationGetRelationName(fk_rel)),
2753 : errhint("This is most likely due to a rule having rewritten the query.")));
2754 :
2755 : /* XXX wouldn't it be clearer to do this part at the caller? */
2756 2465 : if (qkey->constr_queryno != RI_PLAN_CHECK_LOOKUPPK_FROM_PK &&
2757 1529 : expect_OK == SPI_OK_SELECT &&
2758 1529 : (SPI_processed == 0) == (qkey->constr_queryno == RI_PLAN_CHECK_LOOKUPPK))
2759 462 : ri_ReportViolation(riinfo,
2760 : pk_rel, fk_rel,
2761 : newslot ? newslot : oldslot,
2762 : NULL,
2763 : qkey->constr_queryno, is_restrict, false);
2764 :
2765 2003 : return SPI_processed != 0;
2766 : }
2767 :
2768 : /*
2769 : * ri_FastPathCheck
2770 : * Perform per row FK existence check via direct index probe,
2771 : * bypassing SPI.
2772 : *
2773 : * If no matching PK row exists, report the violation via ri_ReportViolation(),
2774 : * otherwise, the function returns normally.
2775 : *
2776 : * Note: This is only used by the ALTER TABLE validation path. Other paths use
2777 : * ri_FastPathBatchAdd().
2778 : */
2779 : static void
2780 44 : ri_FastPathCheck(RI_ConstraintInfo *riinfo,
2781 : Relation fk_rel, TupleTableSlot *newslot)
2782 : {
2783 : Relation pk_rel;
2784 : Relation idx_rel;
2785 : IndexScanDesc scandesc;
2786 : TupleTableSlot *slot;
2787 : Datum pk_vals[INDEX_MAX_KEYS];
2788 : char pk_nulls[INDEX_MAX_KEYS];
2789 : ScanKeyData skey[INDEX_MAX_KEYS];
2790 44 : bool found = false;
2791 : Oid saved_userid;
2792 : int saved_sec_context;
2793 : Snapshot snapshot;
2794 :
2795 : /*
2796 : * Advance the command counter so the snapshot sees the effects of prior
2797 : * triggers in this statement. Mirrors what the SPI path does in
2798 : * ri_PerformCheck().
2799 : */
2800 44 : CommandCounterIncrement();
2801 44 : snapshot = RegisterSnapshot(GetTransactionSnapshot());
2802 :
2803 44 : pk_rel = table_open(riinfo->pk_relid, RowShareLock);
2804 44 : idx_rel = index_open(riinfo->conindid, AccessShareLock);
2805 :
2806 44 : slot = table_slot_create(pk_rel, NULL);
2807 44 : scandesc = index_beginscan(pk_rel, idx_rel,
2808 : snapshot, NULL,
2809 : riinfo->nkeys, 0,
2810 : SO_NONE);
2811 :
2812 44 : GetUserIdAndSecContext(&saved_userid, &saved_sec_context);
2813 44 : SetUserIdAndSecContext(RelationGetForm(pk_rel)->relowner,
2814 : saved_sec_context |
2815 : SECURITY_LOCAL_USERID_CHANGE |
2816 : SECURITY_NOFORCE_RLS);
2817 44 : ri_CheckPermissions(pk_rel);
2818 :
2819 44 : if (riinfo->fpmeta == NULL)
2820 : {
2821 : /* Reload to ensure it's valid. */
2822 8 : riinfo = ri_LoadConstraintInfo(riinfo->constraint_id);
2823 8 : ri_populate_fastpath_metadata(riinfo, 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 : 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 603651 : ri_FastPathBatchAdd(RI_ConstraintInfo *riinfo,
2860 : Relation fk_rel, TupleTableSlot *newslot)
2861 : {
2862 603651 : RI_FastPathEntry *fpentry = ri_FastPathGetEntry(riinfo, fk_rel);
2863 : MemoryContext oldcxt;
2864 :
2865 603651 : oldcxt = MemoryContextSwitchTo(fpentry->flush_cxt);
2866 1207302 : fpentry->batch[fpentry->batch_count] =
2867 603651 : ExecCopySlotHeapTuple(newslot);
2868 603651 : fpentry->batch_count++;
2869 603651 : MemoryContextSwitchTo(oldcxt);
2870 :
2871 603651 : if (fpentry->batch_count >= RI_FASTPATH_BATCH_SIZE)
2872 9392 : ri_FastPathBatchFlush(fpentry, fk_rel, riinfo);
2873 603651 : }
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 11107 : ri_FastPathBatchFlush(RI_FastPathEntry *fpentry, Relation fk_rel,
2886 : RI_ConstraintInfo *riinfo)
2887 : {
2888 11107 : Relation pk_rel = fpentry->pk_rel;
2889 11107 : Relation idx_rel = fpentry->idx_rel;
2890 11107 : 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 11107 : 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 11107 : CommandCounterIncrement();
2912 11107 : 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 11107 : oldcxt = MemoryContextSwitchTo(fpentry->flush_cxt);
2920 :
2921 11107 : scandesc = index_beginscan(pk_rel, idx_rel, snapshot, NULL,
2922 : riinfo->nkeys, 0, SO_NONE);
2923 :
2924 11107 : GetUserIdAndSecContext(&saved_userid, &saved_sec_context);
2925 11107 : 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 11107 : ri_CheckPermissions(pk_rel);
2938 :
2939 11103 : if (riinfo->fpmeta == NULL)
2940 : {
2941 : /* Reload to ensure it's valid. */
2942 943 : riinfo = ri_LoadConstraintInfo(riinfo->constraint_id);
2943 943 : ri_populate_fastpath_metadata(riinfo, fk_rel, idx_rel);
2944 : }
2945 : Assert(riinfo->fpmeta);
2946 :
2947 : /* Skip array overhead for single-row batches. */
2948 11103 : if (riinfo->nkeys == 1 && fpentry->batch_count > 1)
2949 9533 : violation_index = ri_FastPathFlushArray(fpentry, fk_slot, riinfo,
2950 : fk_rel, snapshot, scandesc);
2951 : else
2952 1570 : violation_index = ri_FastPathFlushLoop(fpentry, fk_slot, riinfo,
2953 : fk_rel, snapshot, scandesc);
2954 :
2955 11096 : SetUserIdAndSecContext(saved_userid, saved_sec_context);
2956 11096 : UnregisterSnapshot(snapshot);
2957 11096 : index_endscan(scandesc);
2958 :
2959 11096 : if (violation_index >= 0)
2960 : {
2961 282 : ExecStoreHeapTuple(fpentry->batch[violation_index], fk_slot, false);
2962 282 : ri_ReportViolation(riinfo, pk_rel, fk_rel,
2963 : fk_slot, NULL,
2964 : RI_PLAN_CHECK_LOOKUPPK, false, false);
2965 : }
2966 :
2967 10814 : MemoryContextReset(fpentry->flush_cxt);
2968 10814 : MemoryContextSwitchTo(oldcxt);
2969 :
2970 : /* Reset. */
2971 10814 : fpentry->batch_count = 0;
2972 : }
2973 :
2974 : /*
2975 : * ri_FastPathFlushLoop
2976 : * Multi-column fallback: probe the index once per buffered row.
2977 : *
2978 : * Used for composite foreign keys where SK_SEARCHARRAY does not
2979 : * apply, and also for single-row batches of single-column FKs where
2980 : * the array overhead is not worth it.
2981 : *
2982 : * Returns the index of the first violating row in the batch array, or -1 if
2983 : * all rows are valid.
2984 : */
2985 : static int
2986 1570 : ri_FastPathFlushLoop(RI_FastPathEntry *fpentry, TupleTableSlot *fk_slot,
2987 : const RI_ConstraintInfo *riinfo, Relation fk_rel,
2988 : Snapshot snapshot, IndexScanDesc scandesc)
2989 : {
2990 1570 : Relation pk_rel = fpentry->pk_rel;
2991 1570 : Relation idx_rel = fpentry->idx_rel;
2992 1570 : TupleTableSlot *pk_slot = fpentry->pk_slot;
2993 : Datum pk_vals[INDEX_MAX_KEYS];
2994 : char pk_nulls[INDEX_MAX_KEYS];
2995 : ScanKeyData skey[INDEX_MAX_KEYS];
2996 1570 : bool found = true;
2997 :
2998 3247 : for (int i = 0; i < fpentry->batch_count; i++)
2999 : {
3000 1962 : ExecStoreHeapTuple(fpentry->batch[i], fk_slot, false);
3001 1962 : ri_ExtractValues(fk_rel, fk_slot, riinfo, false, pk_vals, pk_nulls);
3002 1962 : build_index_scankeys(riinfo, idx_rel, pk_vals, pk_nulls, skey);
3003 :
3004 1962 : found = ri_FastPathProbeOne(pk_rel, idx_rel, scandesc, pk_slot,
3005 1962 : snapshot, riinfo, skey, riinfo->nkeys);
3006 :
3007 : /* Report first unmatched row */
3008 1955 : if (!found)
3009 278 : return i;
3010 : }
3011 :
3012 : /* All pass. */
3013 1285 : return -1;
3014 : }
3015 :
3016 : /*
3017 : * ri_FastPathFlushArray
3018 : * Single-column fast path using SK_SEARCHARRAY.
3019 : *
3020 : * Builds an array of FK values and does one index scan with
3021 : * SK_SEARCHARRAY. The index AM sorts and deduplicates the array
3022 : * internally, then walks matching leaf pages in order. Each
3023 : * matched PK tuple is locked and rechecked as before; a matched[]
3024 : * bitmap tracks which batch items were satisfied.
3025 : *
3026 : * Returns the index of the first violating row in the batch array, or -1 if
3027 : * all rows are valid.
3028 : */
3029 : static int
3030 9533 : ri_FastPathFlushArray(RI_FastPathEntry *fpentry, TupleTableSlot *fk_slot,
3031 : const RI_ConstraintInfo *riinfo, Relation fk_rel,
3032 : Snapshot snapshot, IndexScanDesc scandesc)
3033 : {
3034 9533 : FastPathMeta *fpmeta = riinfo->fpmeta;
3035 9533 : Relation pk_rel = fpentry->pk_rel;
3036 9533 : Relation idx_rel = fpentry->idx_rel;
3037 9533 : TupleTableSlot *pk_slot = fpentry->pk_slot;
3038 : Datum search_vals[RI_FASTPATH_BATCH_SIZE];
3039 : bool matched[RI_FASTPATH_BATCH_SIZE];
3040 9533 : int nvals = fpentry->batch_count;
3041 : Datum pk_vals[INDEX_MAX_KEYS];
3042 : char pk_nulls[INDEX_MAX_KEYS];
3043 : ScanKeyData skey[1];
3044 : FmgrInfo *cast_func_finfo;
3045 : FmgrInfo *eq_opr_finfo;
3046 : Oid elem_type;
3047 : int16 elem_len;
3048 : bool elem_byval;
3049 : char elem_align;
3050 : ArrayType *arr;
3051 :
3052 : Assert(fpmeta);
3053 :
3054 9533 : memset(matched, 0, nvals * sizeof(bool));
3055 :
3056 : /*
3057 : * Extract FK values, casting to the operator's expected input type if
3058 : * needed (e.g. int8 FK -> int4 for int48eq).
3059 : */
3060 9533 : cast_func_finfo = &fpmeta->cast_func_finfo[0];
3061 9533 : eq_opr_finfo = &fpmeta->eq_opr_finfo[0];
3062 611202 : for (int i = 0; i < nvals; i++)
3063 : {
3064 601669 : ExecStoreHeapTuple(fpentry->batch[i], fk_slot, false);
3065 601669 : ri_ExtractValues(fk_rel, fk_slot, riinfo, false, pk_vals, pk_nulls);
3066 :
3067 : /* Cast if needed (e.g. int8 FK -> numeric PK) */
3068 601669 : if (OidIsValid(cast_func_finfo->fn_oid))
3069 0 : search_vals[i] = FunctionCall3(cast_func_finfo,
3070 : pk_vals[0],
3071 : Int32GetDatum(-1),
3072 : BoolGetDatum(false));
3073 : else
3074 601669 : search_vals[i] = pk_vals[0];
3075 : }
3076 :
3077 : /*
3078 : * Array element type must match the operator's right-hand input type,
3079 : * which is what the index comparison expects on the search side.
3080 : * ri_populate_fastpath_metadata() stores exactly this via
3081 : * get_op_opfamily_properties(), which returns the operator's right-hand
3082 : * type as the subtype for cross-type operators (e.g. int8 for int48eq)
3083 : * and the common type for same-type operators.
3084 : */
3085 9533 : elem_type = fpmeta->subtypes[0];
3086 : Assert(OidIsValid(elem_type));
3087 9533 : get_typlenbyvalalign(elem_type, &elem_len, &elem_byval, &elem_align);
3088 :
3089 9533 : arr = construct_array(search_vals, nvals,
3090 : elem_type, elem_len, elem_byval, elem_align);
3091 :
3092 : /*
3093 : * Build scan key with SK_SEARCHARRAY. The index AM code will internally
3094 : * sort and deduplicate, then walk leaf pages in order.
3095 : *
3096 : * PK indexes are always btree, which supports SK_SEARCHARRAY.
3097 : *
3098 : * This path handles single-column FKs only, so index_attnos[0] == 1.
3099 : */
3100 : Assert(idx_rel->rd_indam->amsearcharray);
3101 : Assert(fpmeta->index_attnos[0] == 1);
3102 9533 : ScanKeyEntryInitialize(&skey[0],
3103 : SK_SEARCHARRAY,
3104 9533 : fpmeta->index_attnos[0],
3105 9533 : fpmeta->strats[0],
3106 : fpmeta->subtypes[0],
3107 9533 : idx_rel->rd_indcollation[fpmeta->index_attnos[0] - 1],
3108 : fpmeta->regops[0],
3109 : PointerGetDatum(arr));
3110 :
3111 9533 : index_rescan(scandesc, skey, 1, NULL, 0);
3112 :
3113 : /*
3114 : * Walk all matches. The index AM returns them in index order. For each
3115 : * match, find which batch item(s) it satisfies.
3116 : */
3117 420040 : while (index_getnext_slot(scandesc, ForwardScanDirection, pk_slot))
3118 : {
3119 : Datum found_val;
3120 : bool found_null;
3121 : bool concurrently_updated;
3122 : ScanKeyData recheck_skey[1];
3123 :
3124 410507 : if (!ri_LockPKTuple(pk_rel, pk_slot, snapshot, &concurrently_updated))
3125 0 : continue;
3126 :
3127 : /* Extract the PK value from the matched and locked tuple */
3128 410507 : found_val = slot_getattr(pk_slot, riinfo->pk_attnums[0], &found_null);
3129 : Assert(!found_null);
3130 :
3131 410507 : if (concurrently_updated)
3132 : {
3133 : /*
3134 : * Build a single-key scankey for recheck. We need the actual PK
3135 : * value that was found, not the FK search value.
3136 : */
3137 0 : ScanKeyEntryInitialize(&recheck_skey[0], 0, 1,
3138 0 : fpmeta->strats[0],
3139 : fpmeta->subtypes[0],
3140 0 : idx_rel->rd_indcollation[0],
3141 : fpmeta->regops[0],
3142 : found_val);
3143 0 : if (!recheck_matched_pk_tuple(idx_rel, recheck_skey, 1, pk_slot))
3144 0 : continue;
3145 : }
3146 :
3147 : /*
3148 : * Linear scan to mark all batch items matching this PK value.
3149 : * O(batch_size) per match, O(batch_size^2) worst case -- fine for the
3150 : * current batch size of 64.
3151 : */
3152 26657840 : for (int i = 0; i < nvals; i++)
3153 : {
3154 39671800 : if (!matched[i] &&
3155 13424467 : DatumGetBool(FunctionCall2Coll(eq_opr_finfo,
3156 13424467 : idx_rel->rd_indcollation[0],
3157 : found_val,
3158 : search_vals[i])))
3159 601665 : matched[i] = true;
3160 : }
3161 : }
3162 :
3163 : /* Report first unmatched row */
3164 611198 : for (int i = 0; i < nvals; i++)
3165 601669 : if (!matched[i])
3166 4 : return i;
3167 :
3168 : /* All pass. */
3169 9529 : return -1;
3170 : }
3171 :
3172 : /*
3173 : * ri_FastPathProbeOne
3174 : * Probe the PK index for one set of scan keys, lock the matching
3175 : * tuple
3176 : *
3177 : * Returns true if a matching PK row was found, locked, and (if
3178 : * applicable) visible to the transaction snapshot.
3179 : */
3180 : static bool
3181 2006 : ri_FastPathProbeOne(Relation pk_rel, Relation idx_rel,
3182 : IndexScanDesc scandesc, TupleTableSlot *slot,
3183 : Snapshot snapshot, const RI_ConstraintInfo *riinfo,
3184 : ScanKeyData *skey, int nkeys)
3185 : {
3186 2006 : bool found = false;
3187 :
3188 2006 : index_rescan(scandesc, skey, nkeys, NULL, 0);
3189 :
3190 2006 : if (index_getnext_slot(scandesc, ForwardScanDirection, slot))
3191 : {
3192 : bool concurrently_updated;
3193 :
3194 1726 : if (ri_LockPKTuple(pk_rel, slot, snapshot,
3195 : &concurrently_updated))
3196 : {
3197 1718 : if (concurrently_updated)
3198 2 : found = recheck_matched_pk_tuple(idx_rel, skey, nkeys, slot);
3199 : else
3200 1716 : found = true;
3201 : }
3202 : }
3203 :
3204 1999 : return found;
3205 : }
3206 :
3207 : /*
3208 : * ri_LockPKTuple
3209 : * Lock a PK tuple found by the fast-path index scan.
3210 : *
3211 : * Calls table_tuple_lock() directly with handling specific to RI checks.
3212 : * Returns true if the tuple was successfully locked.
3213 : *
3214 : * Sets *concurrently_updated to true if the locked tuple was reached
3215 : * by following an update chain (tmfd.traversed), indicating the caller
3216 : * should recheck the key.
3217 : */
3218 : static bool
3219 412233 : ri_LockPKTuple(Relation pk_rel, TupleTableSlot *slot, Snapshot snap,
3220 : bool *concurrently_updated)
3221 : {
3222 : TM_FailureData tmfd;
3223 : TM_Result result;
3224 412233 : int lockflags = TUPLE_LOCK_FLAG_LOCK_UPDATE_IN_PROGRESS;
3225 :
3226 412233 : *concurrently_updated = false;
3227 :
3228 412233 : if (!IsolationUsesXactSnapshot())
3229 412211 : lockflags |= TUPLE_LOCK_FLAG_FIND_LAST_VERSION;
3230 :
3231 412233 : result = table_tuple_lock(pk_rel, &slot->tts_tid, snap,
3232 : slot, GetCurrentCommandId(false),
3233 : LockTupleKeyShare, LockWaitBlock,
3234 : lockflags, &tmfd);
3235 :
3236 412230 : switch (result)
3237 : {
3238 412225 : case TM_Ok:
3239 412225 : if (tmfd.traversed)
3240 2 : *concurrently_updated = true;
3241 412225 : return true;
3242 :
3243 4 : case TM_Deleted:
3244 4 : if (IsolationUsesXactSnapshot())
3245 3 : ereport(ERROR,
3246 : (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
3247 : errmsg("could not serialize access due to concurrent delete")));
3248 1 : return false;
3249 :
3250 1 : case TM_Updated:
3251 1 : if (IsolationUsesXactSnapshot())
3252 1 : ereport(ERROR,
3253 : (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
3254 : errmsg("could not serialize access due to concurrent update")));
3255 :
3256 : /*
3257 : * In READ COMMITTED, FIND_LAST_VERSION should have chased the
3258 : * chain and returned TM_Ok. Getting here means something
3259 : * unexpected -- fall through to error.
3260 : */
3261 0 : elog(ERROR, "unexpected table_tuple_lock status: %u", result);
3262 : break;
3263 :
3264 0 : case TM_SelfModified:
3265 :
3266 : /*
3267 : * The current command or a later command in this transaction
3268 : * modified the PK row. This shouldn't normally happen during an
3269 : * FK check (we're not modifying pk_rel), but handle it safely by
3270 : * treating the tuple as not found.
3271 : */
3272 0 : return false;
3273 :
3274 0 : case TM_Invisible:
3275 0 : elog(ERROR, "attempted to lock invisible tuple");
3276 : break;
3277 :
3278 0 : default:
3279 0 : elog(ERROR, "unrecognized table_tuple_lock status: %u", result);
3280 : break;
3281 : }
3282 :
3283 : return false; /* keep compiler quiet */
3284 : }
3285 :
3286 : static bool
3287 604485 : ri_fastpath_is_applicable(const RI_ConstraintInfo *riinfo)
3288 : {
3289 : /*
3290 : * Partitioned referenced tables are skipped for simplicity, since they
3291 : * require routing the probe through the correct partition using
3292 : * PartitionDirectory.
3293 : */
3294 604485 : if (riinfo->pk_is_partitioned)
3295 639 : return false;
3296 :
3297 : /*
3298 : * Temporal foreign keys use range overlap and containment semantics (&&,
3299 : * <@, range_agg()) that inherently involve aggregation and multiple-row
3300 : * reasoning, so they stay on the SPI path.
3301 : */
3302 603846 : if (riinfo->hasperiod)
3303 151 : return false;
3304 :
3305 603695 : return true;
3306 : }
3307 :
3308 : /*
3309 : * ri_CheckPermissions
3310 : * Check that the current user has permissions to look into the schema of
3311 : * and SELECT from 'query_rel'
3312 : */
3313 : static void
3314 11151 : ri_CheckPermissions(Relation query_rel)
3315 : {
3316 : AclResult aclresult;
3317 :
3318 : /* USAGE on schema. */
3319 11151 : aclresult = object_aclcheck(NamespaceRelationId,
3320 11151 : RelationGetNamespace(query_rel),
3321 : GetUserId(), ACL_USAGE);
3322 11151 : if (aclresult != ACLCHECK_OK)
3323 0 : aclcheck_error(aclresult, OBJECT_SCHEMA,
3324 0 : get_namespace_name(RelationGetNamespace(query_rel)));
3325 :
3326 : /* SELECT on relation. */
3327 11151 : aclresult = pg_class_aclcheck(RelationGetRelid(query_rel), GetUserId(),
3328 : ACL_SELECT);
3329 11151 : if (aclresult != ACLCHECK_OK)
3330 4 : aclcheck_error(aclresult, OBJECT_TABLE,
3331 4 : RelationGetRelationName(query_rel));
3332 11147 : }
3333 :
3334 : /*
3335 : * recheck_matched_pk_tuple
3336 : * After following an update chain (tmfd.traversed), verify that
3337 : * the locked PK tuple still matches the original search keys.
3338 : *
3339 : * A non-key update (e.g. changing a non-PK column) creates a new tuple version
3340 : * that we've now locked, but the key is unchanged -- that's fine. A key
3341 : * update means the value we were looking for is gone, so we should treat it as
3342 : * not found.
3343 : */
3344 : static bool
3345 2 : recheck_matched_pk_tuple(Relation idxrel, ScanKeyData *skeys, int nkeys,
3346 : TupleTableSlot *new_slot)
3347 : {
3348 : /*
3349 : * TODO: BuildIndexInfo does a syscache lookup + palloc on every call.
3350 : * This only fires on the concurrent-update path (tmfd.traversed), which
3351 : * should be rare, so the cost is acceptable for now. If profiling shows
3352 : * otherwise, cache the IndexInfo in FastPathMeta.
3353 : */
3354 2 : IndexInfo *indexInfo = BuildIndexInfo(idxrel);
3355 : Datum values[INDEX_MAX_KEYS];
3356 : bool isnull[INDEX_MAX_KEYS];
3357 2 : bool matched = true;
3358 :
3359 : /* PK indexes never have these. */
3360 : Assert(indexInfo->ii_Expressions == NIL &&
3361 : indexInfo->ii_ExclusionOps == NULL);
3362 :
3363 : /* Form the index values and isnull flags given the table tuple. */
3364 : Assert(nkeys == indexInfo->ii_NumIndexKeyAttrs);
3365 2 : FormIndexDatum(indexInfo, new_slot, NULL, values, isnull);
3366 3 : for (int i = 0; i < nkeys; i++)
3367 : {
3368 2 : ScanKeyData *skey = &skeys[i];
3369 :
3370 : /* A PK column can never be set to NULL. */
3371 : Assert(!isnull[i]);
3372 2 : if (!DatumGetBool(FunctionCall2Coll(&skey->sk_func,
3373 : skey->sk_collation,
3374 : values[i],
3375 : skey->sk_argument)))
3376 : {
3377 1 : matched = false;
3378 1 : break;
3379 : }
3380 : }
3381 :
3382 2 : return matched;
3383 : }
3384 :
3385 : /*
3386 : * build_index_scankeys
3387 : * Build ScanKeys for a direct index probe of the PK's unique index.
3388 : *
3389 : * Uses cached compare entries, operator procedures, and strategy numbers
3390 : * from ri_populate_fastpath_metadata() rather than looking them up on
3391 : * each invocation. Casts FK values to the operator's expected input
3392 : * type if needed.
3393 : */
3394 : static void
3395 2006 : build_index_scankeys(const RI_ConstraintInfo *riinfo,
3396 : Relation idx_rel, Datum *pk_vals,
3397 : char *pk_nulls, ScanKey skeys)
3398 : {
3399 2006 : FastPathMeta *fpmeta = riinfo->fpmeta;
3400 :
3401 : Assert(fpmeta);
3402 :
3403 : /*
3404 : * May need to cast each of the individual values of the foreign key to
3405 : * the corresponding PK column's type if the equality operator demands it.
3406 : */
3407 4896 : for (int i = 0; i < riinfo->nkeys; i++)
3408 : {
3409 2890 : if (pk_nulls[i] != 'n' &&
3410 2890 : OidIsValid(fpmeta->cast_func_finfo[i].fn_oid))
3411 20 : pk_vals[i] = FunctionCall3(&fpmeta->cast_func_finfo[i],
3412 : pk_vals[i],
3413 : Int32GetDatum(-1), /* typmod */
3414 : BoolGetDatum(false)); /* implicit coercion */
3415 : }
3416 :
3417 : /*
3418 : * Set up ScanKeys for the index scan. This is essentially how
3419 : * ExecIndexBuildScanKeys() sets them up. Use the cached index_attnos and
3420 : * the corresponding collation since FK columns may be in a different
3421 : * order than PK index columns. Place each scan key at the array position
3422 : * corresponding to its index column, since btree requires keys to be
3423 : * ordered by attribute number.
3424 : */
3425 4896 : for (int i = 0; i < riinfo->nkeys; i++)
3426 : {
3427 2890 : AttrNumber pkattrno = fpmeta->index_attnos[i];
3428 2890 : int skey_pos = pkattrno - 1; /* 0-based array position */
3429 :
3430 2890 : ScanKeyEntryInitialize(&skeys[skey_pos], 0, pkattrno,
3431 2890 : fpmeta->strats[i], fpmeta->subtypes[i],
3432 2890 : idx_rel->rd_indcollation[skey_pos], fpmeta->regops[i],
3433 2890 : pk_vals[i]);
3434 : }
3435 2006 : }
3436 :
3437 : /*
3438 : * ri_populate_fastpath_metadata
3439 : * Cache per-key metadata needed by build_index_scankeys().
3440 : *
3441 : * Looks up the compare hash entry, operator procedure OID, and index
3442 : * strategy/subtype for each key column. Called lazily on first use
3443 : * and persists for the lifetime of the RI_ConstraintInfo entry.
3444 : */
3445 : static void
3446 951 : ri_populate_fastpath_metadata(RI_ConstraintInfo *riinfo,
3447 : Relation fk_rel, Relation idx_rel)
3448 : {
3449 : FastPathMeta *fpmeta;
3450 951 : MemoryContext oldcxt = MemoryContextSwitchTo(TopMemoryContext);
3451 :
3452 : Assert(riinfo != NULL && riinfo->valid);
3453 :
3454 951 : fpmeta = palloc_object(FastPathMeta);
3455 2050 : for (int i = 0; i < riinfo->nkeys; i++)
3456 : {
3457 1099 : Oid eq_opr = riinfo->pf_eq_oprs[i];
3458 1099 : Oid typeid = RIAttType(fk_rel, riinfo->fk_attnums[i]);
3459 : Oid lefttype;
3460 1099 : RI_CompareHashEntry *entry = ri_HashCompareOp(eq_opr, typeid);
3461 : int idx_col;
3462 :
3463 : /*
3464 : * Find the index column position for this constraint key. The FK
3465 : * constraint may reference columns in a different order than they
3466 : * appear in the PK index, so we must map pk_attnums[i] to the
3467 : * corresponding index column position.
3468 : */
3469 1271 : for (idx_col = 0; idx_col < riinfo->nkeys; idx_col++)
3470 : {
3471 1271 : if (idx_rel->rd_index->indkey.values[idx_col] == riinfo->pk_attnums[i])
3472 1099 : break;
3473 : }
3474 : Assert(idx_col < riinfo->nkeys);
3475 :
3476 : /* 1-based attribute number */
3477 1099 : fpmeta->index_attnos[i] = idx_col + 1;
3478 :
3479 1099 : fmgr_info_copy(&fpmeta->cast_func_finfo[i], &entry->cast_func_finfo,
3480 : CurrentMemoryContext);
3481 1099 : fmgr_info_copy(&fpmeta->eq_opr_finfo[i], &entry->eq_opr_finfo,
3482 : CurrentMemoryContext);
3483 1099 : fpmeta->regops[i] = get_opcode(eq_opr);
3484 :
3485 1099 : get_op_opfamily_properties(eq_opr,
3486 1099 : idx_rel->rd_opfamily[idx_col],
3487 : false,
3488 : &fpmeta->strats[i],
3489 : &lefttype,
3490 : &fpmeta->subtypes[i]);
3491 : }
3492 :
3493 951 : riinfo->fpmeta = fpmeta;
3494 951 : MemoryContextSwitchTo(oldcxt);
3495 951 : }
3496 :
3497 : /*
3498 : * Extract fields from a tuple into Datum/nulls arrays
3499 : */
3500 : static void
3501 606294 : ri_ExtractValues(Relation rel, TupleTableSlot *slot,
3502 : const RI_ConstraintInfo *riinfo, bool rel_is_pk,
3503 : Datum *vals, char *nulls)
3504 : {
3505 : const int16 *attnums;
3506 : bool isnull;
3507 :
3508 606294 : if (rel_is_pk)
3509 1829 : attnums = riinfo->pk_attnums;
3510 : else
3511 604465 : attnums = riinfo->fk_attnums;
3512 :
3513 1214605 : for (int i = 0; i < riinfo->nkeys; i++)
3514 : {
3515 608311 : vals[i] = slot_getattr(slot, attnums[i], &isnull);
3516 608311 : nulls[i] = isnull ? 'n' : ' ';
3517 : }
3518 606294 : }
3519 :
3520 : /*
3521 : * Produce an error report
3522 : *
3523 : * If the failed constraint was on insert/update to the FK table,
3524 : * we want the key names and values extracted from there, and the error
3525 : * message to look like 'key blah is not present in PK'.
3526 : * Otherwise, the attr names and values come from the PK table and the
3527 : * message looks like 'key blah is still referenced from FK'.
3528 : */
3529 : static void
3530 821 : ri_ReportViolation(const RI_ConstraintInfo *riinfo,
3531 : Relation pk_rel, Relation fk_rel,
3532 : TupleTableSlot *violatorslot, TupleDesc tupdesc,
3533 : int queryno, bool is_restrict, bool partgone)
3534 : {
3535 : StringInfoData key_names;
3536 : StringInfoData key_values;
3537 : bool onfk;
3538 : const int16 *attnums;
3539 : Oid rel_oid;
3540 : AclResult aclresult;
3541 821 : bool has_perm = true;
3542 :
3543 : /*
3544 : * Determine which relation to complain about. If tupdesc wasn't passed
3545 : * by caller, assume the violator tuple came from there.
3546 : */
3547 821 : onfk = (queryno == RI_PLAN_CHECK_LOOKUPPK);
3548 821 : if (onfk)
3549 : {
3550 469 : attnums = riinfo->fk_attnums;
3551 469 : rel_oid = fk_rel->rd_id;
3552 469 : if (tupdesc == NULL)
3553 418 : tupdesc = fk_rel->rd_att;
3554 : }
3555 : else
3556 : {
3557 352 : attnums = riinfo->pk_attnums;
3558 352 : rel_oid = pk_rel->rd_id;
3559 352 : if (tupdesc == NULL)
3560 330 : tupdesc = pk_rel->rd_att;
3561 : }
3562 :
3563 : /*
3564 : * Check permissions- if the user does not have access to view the data in
3565 : * any of the key columns then we don't include the errdetail() below.
3566 : *
3567 : * Check if RLS is enabled on the relation first. If so, we don't return
3568 : * any specifics to avoid leaking data.
3569 : *
3570 : * Check table-level permissions next and, failing that, column-level
3571 : * privileges.
3572 : *
3573 : * When a partition at the referenced side is being detached/dropped, we
3574 : * needn't check, since the user must be the table owner anyway.
3575 : */
3576 821 : if (partgone)
3577 22 : has_perm = true;
3578 799 : else if (check_enable_rls(rel_oid, InvalidOid, true) != RLS_ENABLED)
3579 : {
3580 795 : aclresult = pg_class_aclcheck(rel_oid, GetUserId(), ACL_SELECT);
3581 795 : if (aclresult != ACLCHECK_OK)
3582 : {
3583 : /* Try for column-level permissions */
3584 0 : for (int idx = 0; idx < riinfo->nkeys; idx++)
3585 : {
3586 0 : aclresult = pg_attribute_aclcheck(rel_oid, attnums[idx],
3587 : GetUserId(),
3588 : ACL_SELECT);
3589 :
3590 : /* No access to the key */
3591 0 : if (aclresult != ACLCHECK_OK)
3592 : {
3593 0 : has_perm = false;
3594 0 : break;
3595 : }
3596 : }
3597 : }
3598 : }
3599 : else
3600 4 : has_perm = false;
3601 :
3602 821 : if (has_perm)
3603 : {
3604 : /* Get printable versions of the keys involved */
3605 817 : initStringInfo(&key_names);
3606 817 : initStringInfo(&key_values);
3607 2021 : for (int idx = 0; idx < riinfo->nkeys; idx++)
3608 : {
3609 1204 : int fnum = attnums[idx];
3610 1204 : Form_pg_attribute att = TupleDescAttr(tupdesc, fnum - 1);
3611 : char *name,
3612 : *val;
3613 : Datum datum;
3614 : bool isnull;
3615 :
3616 1204 : name = NameStr(att->attname);
3617 :
3618 1204 : datum = slot_getattr(violatorslot, fnum, &isnull);
3619 1204 : if (!isnull)
3620 : {
3621 : Oid foutoid;
3622 : bool typisvarlena;
3623 :
3624 1204 : getTypeOutputInfo(att->atttypid, &foutoid, &typisvarlena);
3625 1204 : val = OidOutputFunctionCall(foutoid, datum);
3626 : }
3627 : else
3628 0 : val = "null";
3629 :
3630 1204 : if (idx > 0)
3631 : {
3632 387 : appendStringInfoString(&key_names, ", ");
3633 387 : appendStringInfoString(&key_values, ", ");
3634 : }
3635 1204 : appendStringInfoString(&key_names, name);
3636 1204 : appendStringInfoString(&key_values, val);
3637 : }
3638 : }
3639 :
3640 821 : if (partgone)
3641 22 : ereport(ERROR,
3642 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
3643 : errmsg("removing partition \"%s\" violates foreign key constraint \"%s\"",
3644 : RelationGetRelationName(pk_rel),
3645 : NameStr(riinfo->conname)),
3646 : errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
3647 : key_names.data, key_values.data,
3648 : RelationGetRelationName(fk_rel)),
3649 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
3650 799 : else if (onfk)
3651 469 : ereport(ERROR,
3652 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
3653 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
3654 : RelationGetRelationName(fk_rel),
3655 : NameStr(riinfo->conname)),
3656 : has_perm ?
3657 : errdetail("Key (%s)=(%s) is not present in table \"%s\".",
3658 : key_names.data, key_values.data,
3659 : RelationGetRelationName(pk_rel)) :
3660 : errdetail("Key is not present in table \"%s\".",
3661 : RelationGetRelationName(pk_rel)),
3662 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
3663 330 : else if (is_restrict)
3664 20 : ereport(ERROR,
3665 : (errcode(ERRCODE_RESTRICT_VIOLATION),
3666 : errmsg("update or delete on table \"%s\" violates RESTRICT setting of foreign key constraint \"%s\" on table \"%s\"",
3667 : RelationGetRelationName(pk_rel),
3668 : NameStr(riinfo->conname),
3669 : RelationGetRelationName(fk_rel)),
3670 : has_perm ?
3671 : errdetail("Key (%s)=(%s) is referenced from table \"%s\".",
3672 : key_names.data, key_values.data,
3673 : RelationGetRelationName(fk_rel)) :
3674 : errdetail("Key is referenced from table \"%s\".",
3675 : RelationGetRelationName(fk_rel)),
3676 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
3677 : else
3678 310 : ereport(ERROR,
3679 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
3680 : errmsg("update or delete on table \"%s\" violates foreign key constraint \"%s\" on table \"%s\"",
3681 : RelationGetRelationName(pk_rel),
3682 : NameStr(riinfo->conname),
3683 : RelationGetRelationName(fk_rel)),
3684 : has_perm ?
3685 : errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
3686 : key_names.data, key_values.data,
3687 : RelationGetRelationName(fk_rel)) :
3688 : errdetail("Key is still referenced from table \"%s\".",
3689 : RelationGetRelationName(fk_rel)),
3690 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
3691 : }
3692 :
3693 :
3694 : /*
3695 : * ri_NullCheck -
3696 : *
3697 : * Determine the NULL state of all key values in a tuple
3698 : *
3699 : * Returns one of RI_KEYS_ALL_NULL, RI_KEYS_NONE_NULL or RI_KEYS_SOME_NULL.
3700 : */
3701 : static int
3702 606908 : ri_NullCheck(TupleDesc tupDesc,
3703 : TupleTableSlot *slot,
3704 : const RI_ConstraintInfo *riinfo, bool rel_is_pk)
3705 : {
3706 : const int16 *attnums;
3707 606908 : bool allnull = true;
3708 606908 : bool nonenull = true;
3709 :
3710 606908 : if (rel_is_pk)
3711 1533 : attnums = riinfo->pk_attnums;
3712 : else
3713 605375 : attnums = riinfo->fk_attnums;
3714 :
3715 1215937 : for (int i = 0; i < riinfo->nkeys; i++)
3716 : {
3717 609029 : if (slot_attisnull(slot, attnums[i]))
3718 366 : nonenull = false;
3719 : else
3720 608663 : allnull = false;
3721 : }
3722 :
3723 606908 : if (allnull)
3724 182 : return RI_KEYS_ALL_NULL;
3725 :
3726 606726 : if (nonenull)
3727 606590 : return RI_KEYS_NONE_NULL;
3728 :
3729 136 : return RI_KEYS_SOME_NULL;
3730 : }
3731 :
3732 :
3733 : /*
3734 : * ri_InitHashTables -
3735 : *
3736 : * Initialize our internal hash tables.
3737 : */
3738 : static void
3739 264 : ri_InitHashTables(void)
3740 : {
3741 : HASHCTL ctl;
3742 :
3743 264 : ctl.keysize = sizeof(Oid);
3744 264 : ctl.entrysize = sizeof(RI_ConstraintInfo);
3745 264 : ri_constraint_cache = hash_create("RI constraint cache",
3746 : RI_INIT_CONSTRAINTHASHSIZE,
3747 : &ctl, HASH_ELEM | HASH_BLOBS);
3748 :
3749 : /* Arrange to flush cache on pg_constraint changes */
3750 264 : CacheRegisterSyscacheCallback(CONSTROID,
3751 : InvalidateConstraintCacheCallBack,
3752 : (Datum) 0);
3753 :
3754 264 : ctl.keysize = sizeof(RI_QueryKey);
3755 264 : ctl.entrysize = sizeof(RI_QueryHashEntry);
3756 264 : ri_query_cache = hash_create("RI query cache",
3757 : RI_INIT_QUERYHASHSIZE,
3758 : &ctl, HASH_ELEM | HASH_BLOBS);
3759 :
3760 264 : ctl.keysize = sizeof(RI_CompareKey);
3761 264 : ctl.entrysize = sizeof(RI_CompareHashEntry);
3762 264 : ri_compare_cache = hash_create("RI compare cache",
3763 : RI_INIT_QUERYHASHSIZE,
3764 : &ctl, HASH_ELEM | HASH_BLOBS);
3765 264 : }
3766 :
3767 :
3768 : /*
3769 : * ri_FetchPreparedPlan -
3770 : *
3771 : * Lookup for a query key in our private hash table of prepared
3772 : * and saved SPI execution plans. Return the plan if found or NULL.
3773 : */
3774 : static SPIPlanPtr
3775 2475 : ri_FetchPreparedPlan(RI_QueryKey *key)
3776 : {
3777 : RI_QueryHashEntry *entry;
3778 : SPIPlanPtr plan;
3779 :
3780 : /*
3781 : * On the first call initialize the hashtable
3782 : */
3783 2475 : if (!ri_query_cache)
3784 0 : ri_InitHashTables();
3785 :
3786 : /*
3787 : * Lookup for the key
3788 : */
3789 2475 : entry = (RI_QueryHashEntry *) hash_search(ri_query_cache,
3790 : key,
3791 : HASH_FIND, NULL);
3792 2475 : if (entry == NULL)
3793 1020 : return NULL;
3794 :
3795 : /*
3796 : * Check whether the plan is still valid. If it isn't, we don't want to
3797 : * simply rely on plancache.c to regenerate it; rather we should start
3798 : * from scratch and rebuild the query text too. This is to cover cases
3799 : * such as table/column renames. We depend on the plancache machinery to
3800 : * detect possible invalidations, though.
3801 : *
3802 : * CAUTION: this check is only trustworthy if the caller has already
3803 : * locked both FK and PK rels.
3804 : */
3805 1455 : plan = entry->plan;
3806 1455 : if (plan && SPI_plan_is_valid(plan))
3807 1287 : return plan;
3808 :
3809 : /*
3810 : * Otherwise we might as well flush the cached plan now, to free a little
3811 : * memory space before we make a new one.
3812 : */
3813 168 : entry->plan = NULL;
3814 168 : if (plan)
3815 168 : SPI_freeplan(plan);
3816 :
3817 168 : return NULL;
3818 : }
3819 :
3820 :
3821 : /*
3822 : * ri_HashPreparedPlan -
3823 : *
3824 : * Add another plan to our private SPI query plan hashtable.
3825 : */
3826 : static void
3827 1188 : ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan)
3828 : {
3829 : RI_QueryHashEntry *entry;
3830 : bool found;
3831 :
3832 : /*
3833 : * On the first call initialize the hashtable
3834 : */
3835 1188 : if (!ri_query_cache)
3836 0 : ri_InitHashTables();
3837 :
3838 : /*
3839 : * Add the new plan. We might be overwriting an entry previously found
3840 : * invalid by ri_FetchPreparedPlan.
3841 : */
3842 1188 : entry = (RI_QueryHashEntry *) hash_search(ri_query_cache,
3843 : key,
3844 : HASH_ENTER, &found);
3845 : Assert(!found || entry->plan == NULL);
3846 1188 : entry->plan = plan;
3847 1188 : }
3848 :
3849 :
3850 : /*
3851 : * ri_KeysEqual -
3852 : *
3853 : * Check if all key values in OLD and NEW are "equivalent":
3854 : * For normal FKs we check for equality.
3855 : * For temporal FKs we check that the PK side is a superset of its old value,
3856 : * or the FK side is a subset of its old value.
3857 : *
3858 : * Note: at some point we might wish to redefine this as checking for
3859 : * "IS NOT DISTINCT" rather than "=", that is, allow two nulls to be
3860 : * considered equal. Currently there is no need since all callers have
3861 : * previously found at least one of the rows to contain no nulls.
3862 : */
3863 : static bool
3864 1423 : ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot,
3865 : const RI_ConstraintInfo *riinfo, bool rel_is_pk)
3866 : {
3867 : const int16 *attnums;
3868 :
3869 1423 : if (rel_is_pk)
3870 936 : attnums = riinfo->pk_attnums;
3871 : else
3872 487 : attnums = riinfo->fk_attnums;
3873 :
3874 : /* XXX: could be worthwhile to fetch all necessary attrs at once */
3875 2193 : for (int i = 0; i < riinfo->nkeys; i++)
3876 : {
3877 : Datum oldvalue;
3878 : Datum newvalue;
3879 : bool isnull;
3880 :
3881 : /*
3882 : * Get one attribute's oldvalue. If it is NULL - they're not equal.
3883 : */
3884 1643 : oldvalue = slot_getattr(oldslot, attnums[i], &isnull);
3885 1643 : if (isnull)
3886 873 : return false;
3887 :
3888 : /*
3889 : * Get one attribute's newvalue. If it is NULL - they're not equal.
3890 : */
3891 1625 : newvalue = slot_getattr(newslot, attnums[i], &isnull);
3892 1625 : if (isnull)
3893 0 : return false;
3894 :
3895 1625 : if (rel_is_pk)
3896 : {
3897 : /*
3898 : * If we are looking at the PK table, then do a bytewise
3899 : * comparison. We must propagate PK changes if the value is
3900 : * changed to one that "looks" different but would compare as
3901 : * equal using the equality operator. This only makes a
3902 : * difference for ON UPDATE CASCADE, but for consistency we treat
3903 : * all changes to the PK the same.
3904 : */
3905 1100 : CompactAttribute *att = TupleDescCompactAttr(oldslot->tts_tupleDescriptor, attnums[i] - 1);
3906 :
3907 1100 : if (!datum_image_eq(oldvalue, newvalue, att->attbyval, att->attlen))
3908 648 : return false;
3909 : }
3910 : else
3911 : {
3912 : Oid eq_opr;
3913 :
3914 : /*
3915 : * When comparing the PERIOD columns we can skip the check
3916 : * whenever the referencing column stayed equal or shrank, so test
3917 : * with the contained-by operator instead.
3918 : */
3919 525 : if (riinfo->hasperiod && i == riinfo->nkeys - 1)
3920 32 : eq_opr = riinfo->period_contained_by_oper;
3921 : else
3922 493 : eq_opr = riinfo->ff_eq_oprs[i];
3923 :
3924 : /*
3925 : * For the FK table, compare with the appropriate equality
3926 : * operator. Changes that compare equal will still satisfy the
3927 : * constraint after the update.
3928 : */
3929 525 : if (!ri_CompareWithCast(eq_opr, RIAttType(rel, attnums[i]), RIAttCollation(rel, attnums[i]),
3930 : newvalue, oldvalue))
3931 207 : return false;
3932 : }
3933 : }
3934 :
3935 550 : return true;
3936 : }
3937 :
3938 :
3939 : /*
3940 : * ri_CompareWithCast -
3941 : *
3942 : * Call the appropriate comparison operator for two values.
3943 : * Normally this is equality, but for the PERIOD part of foreign keys
3944 : * it is ContainedBy, so the order of lhs vs rhs is significant.
3945 : * See below for how the collation is applied.
3946 : *
3947 : * NB: we have already checked that neither value is null.
3948 : */
3949 : static bool
3950 525 : ri_CompareWithCast(Oid eq_opr, Oid typeid, Oid collid,
3951 : Datum lhs, Datum rhs)
3952 : {
3953 525 : RI_CompareHashEntry *entry = ri_HashCompareOp(eq_opr, typeid);
3954 :
3955 : /* Do we need to cast the values? */
3956 525 : if (OidIsValid(entry->cast_func_finfo.fn_oid))
3957 : {
3958 8 : lhs = FunctionCall3(&entry->cast_func_finfo,
3959 : lhs,
3960 : Int32GetDatum(-1), /* typmod */
3961 : BoolGetDatum(false)); /* implicit coercion */
3962 8 : rhs = FunctionCall3(&entry->cast_func_finfo,
3963 : rhs,
3964 : Int32GetDatum(-1), /* typmod */
3965 : BoolGetDatum(false)); /* implicit coercion */
3966 : }
3967 :
3968 : /*
3969 : * Apply the comparison operator.
3970 : *
3971 : * Note: This function is part of a call stack that determines whether an
3972 : * update to a row is significant enough that it needs checking or action
3973 : * on the other side of a foreign-key constraint. Therefore, the
3974 : * comparison here would need to be done with the collation of the *other*
3975 : * table. For simplicity (e.g., we might not even have the other table
3976 : * open), we'll use our own collation. This is fine because we require
3977 : * that both collations have the same notion of equality (either they are
3978 : * both deterministic or else they are both the same).
3979 : *
3980 : * With range/multirangetypes, the collation of the base type is stored as
3981 : * part of the rangetype (pg_range.rngcollation), and always used, so
3982 : * there is no danger of inconsistency even using a non-equals operator.
3983 : * But if we support arbitrary types with PERIOD, we should perhaps just
3984 : * always force a re-check.
3985 : */
3986 525 : return DatumGetBool(FunctionCall2Coll(&entry->eq_opr_finfo, collid, lhs, rhs));
3987 : }
3988 :
3989 : /*
3990 : * ri_HashCompareOp -
3991 : *
3992 : * Look up or create a cache entry for the given equality operator and
3993 : * the caller's value type (typeid). The entry holds the operator's
3994 : * FmgrInfo and, if typeid doesn't match what the operator expects as
3995 : * its right-hand input, a cast function to coerce the value before
3996 : * comparison.
3997 : */
3998 : static RI_CompareHashEntry *
3999 1624 : ri_HashCompareOp(Oid eq_opr, Oid typeid)
4000 : {
4001 : RI_CompareKey key;
4002 : RI_CompareHashEntry *entry;
4003 : bool found;
4004 :
4005 : /*
4006 : * On the first call initialize the hashtable
4007 : */
4008 1624 : if (!ri_compare_cache)
4009 0 : ri_InitHashTables();
4010 :
4011 : /*
4012 : * Find or create a hash entry. Note we're assuming RI_CompareKey
4013 : * contains no struct padding.
4014 : */
4015 1624 : key.eq_opr = eq_opr;
4016 1624 : key.typeid = typeid;
4017 1624 : entry = (RI_CompareHashEntry *) hash_search(ri_compare_cache,
4018 : &key,
4019 : HASH_ENTER, &found);
4020 1624 : if (!found)
4021 256 : entry->valid = false;
4022 :
4023 : /*
4024 : * If not already initialized, do so. Since we'll keep this hash entry
4025 : * for the life of the backend, put any subsidiary info for the function
4026 : * cache structs into TopMemoryContext.
4027 : */
4028 1624 : if (!entry->valid)
4029 : {
4030 : Oid lefttype,
4031 : righttype,
4032 : castfunc;
4033 : CoercionPathType pathtype;
4034 :
4035 : /* We always need to know how to call the equality operator */
4036 256 : fmgr_info_cxt(get_opcode(eq_opr), &entry->eq_opr_finfo,
4037 : TopMemoryContext);
4038 :
4039 : /*
4040 : * If we chose to use a cast from FK to PK type, we may have to apply
4041 : * the cast function to get to the operator's input type.
4042 : *
4043 : * XXX eventually it would be good to support array-coercion cases
4044 : * here and in ri_CompareWithCast(). At the moment there is no point
4045 : * because cases involving nonidentical array types will be rejected
4046 : * at constraint creation time.
4047 : *
4048 : * XXX perhaps also consider supporting CoerceViaIO? No need at the
4049 : * moment since that will never be generated for implicit coercions.
4050 : */
4051 256 : op_input_types(eq_opr, &lefttype, &righttype);
4052 :
4053 : /*
4054 : * pf_eq_oprs (used by the fast path) can be cross-type when the FK
4055 : * and PK columns differ in type, e.g. int48eq for int4 PK / int8 FK.
4056 : * If the FK column's type already matches what the operator expects
4057 : * as its right-hand input, no cast is needed.
4058 : */
4059 256 : if (typeid == righttype)
4060 232 : castfunc = InvalidOid; /* simplest case */
4061 : else
4062 : {
4063 24 : pathtype = find_coercion_pathway(lefttype, typeid,
4064 : COERCION_IMPLICIT,
4065 : &castfunc);
4066 24 : if (pathtype != COERCION_PATH_FUNC &&
4067 : pathtype != COERCION_PATH_RELABELTYPE)
4068 : {
4069 : /*
4070 : * The declared input type of the eq_opr might be a
4071 : * polymorphic type such as ANYARRAY or ANYENUM, or other
4072 : * special cases such as RECORD; find_coercion_pathway
4073 : * currently doesn't subsume these special cases.
4074 : */
4075 16 : if (!IsBinaryCoercible(typeid, lefttype))
4076 0 : elog(ERROR, "no conversion function from %s to %s",
4077 : format_type_be(typeid),
4078 : format_type_be(lefttype));
4079 : }
4080 : }
4081 256 : if (OidIsValid(castfunc))
4082 8 : fmgr_info_cxt(castfunc, &entry->cast_func_finfo,
4083 : TopMemoryContext);
4084 : else
4085 248 : entry->cast_func_finfo.fn_oid = InvalidOid;
4086 256 : entry->valid = true;
4087 : }
4088 :
4089 1624 : return entry;
4090 : }
4091 :
4092 :
4093 : /*
4094 : * Given a trigger function OID, determine whether it is an RI trigger,
4095 : * and if so whether it is attached to PK or FK relation.
4096 : */
4097 : int
4098 5788 : RI_FKey_trigger_type(Oid tgfoid)
4099 : {
4100 5788 : switch (tgfoid)
4101 : {
4102 2033 : case F_RI_FKEY_CASCADE_DEL:
4103 : case F_RI_FKEY_CASCADE_UPD:
4104 : case F_RI_FKEY_RESTRICT_DEL:
4105 : case F_RI_FKEY_RESTRICT_UPD:
4106 : case F_RI_FKEY_SETNULL_DEL:
4107 : case F_RI_FKEY_SETNULL_UPD:
4108 : case F_RI_FKEY_SETDEFAULT_DEL:
4109 : case F_RI_FKEY_SETDEFAULT_UPD:
4110 : case F_RI_FKEY_NOACTION_DEL:
4111 : case F_RI_FKEY_NOACTION_UPD:
4112 2033 : return RI_TRIGGER_PK;
4113 :
4114 1850 : case F_RI_FKEY_CHECK_INS:
4115 : case F_RI_FKEY_CHECK_UPD:
4116 1850 : return RI_TRIGGER_FK;
4117 : }
4118 :
4119 1905 : return RI_TRIGGER_NONE;
4120 : }
4121 :
4122 : /*
4123 : * ri_FastPathEndBatch
4124 : * Flush remaining rows and tear down cached state.
4125 : *
4126 : * Registered as an AfterTriggerBatchCallback. Note: the flush can
4127 : * do real work (CCI, security context switch, index probes) and can
4128 : * throw ERROR on a constraint violation. If that happens,
4129 : * ri_FastPathTeardown never runs; ResourceOwner + XactCallback
4130 : * handle resource cleanup on the abort path.
4131 : */
4132 : static void
4133 1497 : ri_FastPathEndBatch(void *arg)
4134 : {
4135 : HASH_SEQ_STATUS status;
4136 : RI_FastPathEntry *entry;
4137 :
4138 1497 : if (ri_fastpath_cache == NULL)
4139 0 : return;
4140 :
4141 : /* Flush any partial batches -- can throw ERROR */
4142 1497 : hash_seq_init(&status, ri_fastpath_cache);
4143 4416 : while ((entry = hash_seq_search(&status)) != NULL)
4144 : {
4145 1715 : if (entry->batch_count > 0)
4146 : {
4147 1715 : Relation fk_rel = table_open(entry->fk_relid, AccessShareLock);
4148 1715 : RI_ConstraintInfo *riinfo = ri_LoadConstraintInfo(entry->conoid);
4149 :
4150 1715 : ri_FastPathBatchFlush(entry, fk_rel, riinfo);
4151 1422 : table_close(fk_rel, NoLock);
4152 : }
4153 : }
4154 :
4155 1204 : ri_FastPathTeardown();
4156 : }
4157 :
4158 : /*
4159 : * ri_FastPathTeardown
4160 : * Tear down all cached fast-path state.
4161 : *
4162 : * Called from ri_FastPathEndBatch() after flushing any remaining rows.
4163 : */
4164 : static void
4165 1204 : ri_FastPathTeardown(void)
4166 : {
4167 : HASH_SEQ_STATUS status;
4168 : RI_FastPathEntry *entry;
4169 :
4170 1204 : if (ri_fastpath_cache == NULL)
4171 0 : return;
4172 :
4173 1204 : hash_seq_init(&status, ri_fastpath_cache);
4174 3818 : while ((entry = hash_seq_search(&status)) != NULL)
4175 : {
4176 1410 : if (entry->idx_rel)
4177 1410 : index_close(entry->idx_rel, NoLock);
4178 1410 : if (entry->pk_rel)
4179 1410 : table_close(entry->pk_rel, NoLock);
4180 1410 : if (entry->pk_slot)
4181 1410 : ExecDropSingleTupleTableSlot(entry->pk_slot);
4182 1410 : if (entry->fk_slot)
4183 1410 : ExecDropSingleTupleTableSlot(entry->fk_slot);
4184 1410 : if (entry->flush_cxt)
4185 1410 : MemoryContextDelete(entry->flush_cxt);
4186 : }
4187 :
4188 1204 : hash_destroy(ri_fastpath_cache);
4189 1204 : ri_fastpath_cache = NULL;
4190 1204 : ri_fastpath_callback_registered = false;
4191 : }
4192 :
4193 : static bool ri_fastpath_xact_callback_registered = false;
4194 :
4195 : static void
4196 73555 : ri_FastPathXactCallback(XactEvent event, void *arg)
4197 : {
4198 : /*
4199 : * On abort, ResourceOwner already released relations; on commit,
4200 : * ri_FastPathTeardown already ran. Either way, just NULL the static
4201 : * pointers so they don't dangle into the next transaction.
4202 : */
4203 73555 : ri_fastpath_cache = NULL;
4204 73555 : ri_fastpath_callback_registered = false;
4205 73555 : }
4206 :
4207 : static void
4208 347 : ri_FastPathSubXactCallback(SubXactEvent event, SubTransactionId mySubid,
4209 : SubTransactionId parentSubid, void *arg)
4210 : {
4211 347 : if (event == SUBXACT_EVENT_ABORT_SUB)
4212 : {
4213 : /*
4214 : * ResourceOwner already released relations. NULL the static pointers
4215 : * so the still-registered batch callback becomes a no-op for the rest
4216 : * of this transaction.
4217 : */
4218 94 : ri_fastpath_cache = NULL;
4219 94 : ri_fastpath_callback_registered = false;
4220 : }
4221 347 : }
4222 :
4223 : /*
4224 : * ri_FastPathGetEntry
4225 : * Look up or create a per-batch cache entry for the given constraint.
4226 : *
4227 : * On first call for a constraint within a batch: opens pk_rel and the index,
4228 : * allocates slots for both FK row and the looked up PK row, and registers the
4229 : * cleanup callback.
4230 : *
4231 : * On subsequent calls: returns the existing entry.
4232 : */
4233 : static RI_FastPathEntry *
4234 603651 : ri_FastPathGetEntry(const RI_ConstraintInfo *riinfo, Relation fk_rel)
4235 : {
4236 : RI_FastPathEntry *entry;
4237 : bool found;
4238 :
4239 : /* Create hash table on first use in this batch */
4240 603651 : if (ri_fastpath_cache == NULL)
4241 : {
4242 : HASHCTL ctl;
4243 :
4244 1497 : if (!ri_fastpath_xact_callback_registered)
4245 : {
4246 213 : RegisterXactCallback(ri_FastPathXactCallback, NULL);
4247 213 : RegisterSubXactCallback(ri_FastPathSubXactCallback, NULL);
4248 213 : ri_fastpath_xact_callback_registered = true;
4249 : }
4250 :
4251 1497 : ctl.keysize = sizeof(Oid);
4252 1497 : ctl.entrysize = sizeof(RI_FastPathEntry);
4253 1497 : ctl.hcxt = TopTransactionContext;
4254 1497 : ri_fastpath_cache = hash_create("RI fast-path cache",
4255 : 16,
4256 : &ctl,
4257 : HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
4258 : }
4259 :
4260 603651 : entry = hash_search(ri_fastpath_cache, &riinfo->constraint_id,
4261 : HASH_ENTER, &found);
4262 :
4263 603651 : if (!found)
4264 : {
4265 : MemoryContext oldcxt;
4266 :
4267 : /*
4268 : * Zero out non-key fields so ri_FastPathTeardown is safe if we error
4269 : * out during partial initialization below.
4270 : */
4271 1731 : memset(((char *) entry) + offsetof(RI_FastPathEntry, pk_rel), 0,
4272 : sizeof(RI_FastPathEntry) - offsetof(RI_FastPathEntry, pk_rel));
4273 :
4274 1731 : oldcxt = MemoryContextSwitchTo(TopTransactionContext);
4275 :
4276 1731 : entry->fk_relid = RelationGetRelid(fk_rel);
4277 :
4278 : /*
4279 : * Open PK table and its unique index.
4280 : *
4281 : * RowShareLock on pk_rel matches what the SPI path's SELECT ... FOR
4282 : * KEY SHARE would acquire as a relation-level lock. AccessShareLock
4283 : * on the index is standard for index scans.
4284 : *
4285 : * We don't release these locks until end of transaction, matching SPI
4286 : * behavior.
4287 : */
4288 1731 : entry->pk_rel = table_open(riinfo->pk_relid, RowShareLock);
4289 1731 : entry->idx_rel = index_open(riinfo->conindid, AccessShareLock);
4290 1731 : entry->pk_slot = table_slot_create(entry->pk_rel, NULL);
4291 :
4292 : /*
4293 : * Must be TTSOpsHeapTuple because ExecStoreHeapTuple() is used to
4294 : * load entries from batch[] into this slot for value extraction.
4295 : */
4296 1731 : entry->fk_slot = MakeSingleTupleTableSlot(RelationGetDescr(fk_rel),
4297 : &TTSOpsHeapTuple);
4298 :
4299 1731 : entry->flush_cxt = AllocSetContextCreate(TopTransactionContext,
4300 : "RI fast path flush temporary context",
4301 : ALLOCSET_SMALL_SIZES);
4302 1731 : MemoryContextSwitchTo(oldcxt);
4303 :
4304 : /* Ensure cleanup at end of this trigger-firing batch */
4305 1731 : if (!ri_fastpath_callback_registered)
4306 : {
4307 1497 : RegisterAfterTriggerBatchCallback(ri_FastPathEndBatch, NULL);
4308 1497 : ri_fastpath_callback_registered = true;
4309 : }
4310 : }
4311 :
4312 603651 : return entry;
4313 : }
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