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ri_triggers.c
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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) 1996-2023, PostgreSQL Global Development Group
18  *
19  * src/backend/utils/adt/ri_triggers.c
20  *
21  *-------------------------------------------------------------------------
22  */
23 
24 #include "postgres.h"
25 
26 #include "access/htup_details.h"
27 #include "access/sysattr.h"
28 #include "access/table.h"
29 #include "access/tableam.h"
30 #include "access/xact.h"
31 #include "catalog/pg_collation.h"
32 #include "catalog/pg_constraint.h"
33 #include "catalog/pg_operator.h"
34 #include "catalog/pg_type.h"
35 #include "commands/trigger.h"
36 #include "executor/executor.h"
37 #include "executor/spi.h"
38 #include "lib/ilist.h"
39 #include "miscadmin.h"
40 #include "parser/parse_coerce.h"
41 #include "parser/parse_relation.h"
42 #include "storage/bufmgr.h"
43 #include "utils/acl.h"
44 #include "utils/builtins.h"
45 #include "utils/datum.h"
46 #include "utils/fmgroids.h"
47 #include "utils/guc.h"
48 #include "utils/inval.h"
49 #include "utils/lsyscache.h"
50 #include "utils/memutils.h"
51 #include "utils/rel.h"
52 #include "utils/rls.h"
53 #include "utils/ruleutils.h"
54 #include "utils/snapmgr.h"
55 #include "utils/syscache.h"
56 
57 /*
58  * Local definitions
59  */
60 
61 #define RI_MAX_NUMKEYS INDEX_MAX_KEYS
62 
63 #define RI_INIT_CONSTRAINTHASHSIZE 64
64 #define RI_INIT_QUERYHASHSIZE (RI_INIT_CONSTRAINTHASHSIZE * 4)
65 
66 #define RI_KEYS_ALL_NULL 0
67 #define RI_KEYS_SOME_NULL 1
68 #define RI_KEYS_NONE_NULL 2
69 
70 /* RI query type codes */
71 /* these queries are executed against the PK (referenced) table: */
72 #define RI_PLAN_CHECK_LOOKUPPK 1
73 #define RI_PLAN_CHECK_LOOKUPPK_FROM_PK 2
74 #define RI_PLAN_LAST_ON_PK RI_PLAN_CHECK_LOOKUPPK_FROM_PK
75 /* these queries are executed against the FK (referencing) table: */
76 #define RI_PLAN_CASCADE_ONDELETE 3
77 #define RI_PLAN_CASCADE_ONUPDATE 4
78 /* For RESTRICT, the same plan can be used for both ON DELETE and ON UPDATE triggers. */
79 #define RI_PLAN_RESTRICT 5
80 #define RI_PLAN_SETNULL_ONDELETE 6
81 #define RI_PLAN_SETNULL_ONUPDATE 7
82 #define RI_PLAN_SETDEFAULT_ONDELETE 8
83 #define RI_PLAN_SETDEFAULT_ONUPDATE 9
84 
85 #define MAX_QUOTED_NAME_LEN (NAMEDATALEN*2+3)
86 #define MAX_QUOTED_REL_NAME_LEN (MAX_QUOTED_NAME_LEN*2)
87 
88 #define RIAttName(rel, attnum) NameStr(*attnumAttName(rel, attnum))
89 #define RIAttType(rel, attnum) attnumTypeId(rel, attnum)
90 #define RIAttCollation(rel, attnum) attnumCollationId(rel, attnum)
91 
92 #define RI_TRIGTYPE_INSERT 1
93 #define RI_TRIGTYPE_UPDATE 2
94 #define RI_TRIGTYPE_DELETE 3
95 
96 
97 /*
98  * RI_ConstraintInfo
99  *
100  * Information extracted from an FK pg_constraint entry. This is cached in
101  * ri_constraint_cache.
102  */
103 typedef struct RI_ConstraintInfo
104 {
105  Oid constraint_id; /* OID of pg_constraint entry (hash key) */
106  bool valid; /* successfully initialized? */
107  Oid constraint_root_id; /* OID of topmost ancestor constraint;
108  * same as constraint_id if not inherited */
109  uint32 oidHashValue; /* hash value of constraint_id */
110  uint32 rootHashValue; /* hash value of constraint_root_id */
111  NameData conname; /* name of the FK constraint */
112  Oid pk_relid; /* referenced relation */
113  Oid fk_relid; /* referencing relation */
114  char confupdtype; /* foreign key's ON UPDATE action */
115  char confdeltype; /* foreign key's ON DELETE action */
116  int ndelsetcols; /* number of columns referenced in ON DELETE
117  * SET clause */
118  int16 confdelsetcols[RI_MAX_NUMKEYS]; /* attnums of cols to set on
119  * delete */
120  char confmatchtype; /* foreign key's match type */
121  int nkeys; /* number of key columns */
122  int16 pk_attnums[RI_MAX_NUMKEYS]; /* attnums of referenced cols */
123  int16 fk_attnums[RI_MAX_NUMKEYS]; /* attnums of referencing cols */
124  Oid pf_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (PK = FK) */
125  Oid pp_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (PK = PK) */
126  Oid ff_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (FK = FK) */
127  dlist_node valid_link; /* Link in list of valid entries */
129 
130 /*
131  * RI_QueryKey
132  *
133  * The key identifying a prepared SPI plan in our query hashtable
134  */
135 typedef struct RI_QueryKey
136 {
137  Oid constr_id; /* OID of pg_constraint entry */
138  int32 constr_queryno; /* query type ID, see RI_PLAN_XXX above */
140 
141 /*
142  * RI_QueryHashEntry
143  */
144 typedef struct RI_QueryHashEntry
145 {
149 
150 /*
151  * RI_CompareKey
152  *
153  * The key identifying an entry showing how to compare two values
154  */
155 typedef struct RI_CompareKey
156 {
157  Oid eq_opr; /* the equality operator to apply */
158  Oid typeid; /* the data type to apply it to */
160 
161 /*
162  * RI_CompareHashEntry
163  */
164 typedef struct RI_CompareHashEntry
165 {
167  bool valid; /* successfully initialized? */
168  FmgrInfo eq_opr_finfo; /* call info for equality fn */
169  FmgrInfo cast_func_finfo; /* in case we must coerce input */
171 
172 
173 /*
174  * Local data
175  */
176 static HTAB *ri_constraint_cache = NULL;
177 static HTAB *ri_query_cache = NULL;
178 static HTAB *ri_compare_cache = NULL;
180 
181 
182 /*
183  * Local function prototypes
184  */
185 static bool ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
186  TupleTableSlot *oldslot,
187  const RI_ConstraintInfo *riinfo);
188 static Datum ri_restrict(TriggerData *trigdata, bool is_no_action);
189 static Datum ri_set(TriggerData *trigdata, bool is_set_null, int tgkind);
190 static void quoteOneName(char *buffer, const char *name);
191 static void quoteRelationName(char *buffer, Relation rel);
192 static void ri_GenerateQual(StringInfo buf,
193  const char *sep,
194  const char *leftop, Oid leftoptype,
195  Oid opoid,
196  const char *rightop, Oid rightoptype);
197 static void ri_GenerateQualCollation(StringInfo buf, Oid collation);
198 static int ri_NullCheck(TupleDesc tupDesc, TupleTableSlot *slot,
199  const RI_ConstraintInfo *riinfo, bool rel_is_pk);
200 static void ri_BuildQueryKey(RI_QueryKey *key,
201  const RI_ConstraintInfo *riinfo,
202  int32 constr_queryno);
203 static bool ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot,
204  const RI_ConstraintInfo *riinfo, bool rel_is_pk);
205 static bool ri_AttributesEqual(Oid eq_opr, Oid typeid,
206  Datum oldvalue, Datum newvalue);
207 
208 static void ri_InitHashTables(void);
209 static void InvalidateConstraintCacheCallBack(Datum arg, int cacheid, uint32 hashvalue);
212 static RI_CompareHashEntry *ri_HashCompareOp(Oid eq_opr, Oid typeid);
213 
214 static void ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname,
215  int tgkind);
216 static const RI_ConstraintInfo *ri_FetchConstraintInfo(Trigger *trigger,
217  Relation trig_rel, bool rel_is_pk);
218 static const RI_ConstraintInfo *ri_LoadConstraintInfo(Oid constraintOid);
219 static Oid get_ri_constraint_root(Oid constrOid);
220 static SPIPlanPtr ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
221  RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel);
222 static bool ri_PerformCheck(const RI_ConstraintInfo *riinfo,
223  RI_QueryKey *qkey, SPIPlanPtr qplan,
224  Relation fk_rel, Relation pk_rel,
225  TupleTableSlot *oldslot, TupleTableSlot *newslot,
226  bool detectNewRows, int expect_OK);
227 static void ri_ExtractValues(Relation rel, TupleTableSlot *slot,
228  const RI_ConstraintInfo *riinfo, bool rel_is_pk,
229  Datum *vals, char *nulls);
230 static void ri_ReportViolation(const RI_ConstraintInfo *riinfo,
231  Relation pk_rel, Relation fk_rel,
232  TupleTableSlot *violatorslot, TupleDesc tupdesc,
233  int queryno, bool partgone) pg_attribute_noreturn();
234 
235 
236 /*
237  * RI_FKey_check -
238  *
239  * Check foreign key existence (combined for INSERT and UPDATE).
240  */
241 static Datum
243 {
244  const RI_ConstraintInfo *riinfo;
245  Relation fk_rel;
246  Relation pk_rel;
247  TupleTableSlot *newslot;
248  RI_QueryKey qkey;
249  SPIPlanPtr qplan;
250 
251  riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
252  trigdata->tg_relation, false);
253 
254  if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
255  newslot = trigdata->tg_newslot;
256  else
257  newslot = trigdata->tg_trigslot;
258 
259  /*
260  * We should not even consider checking the row if it is no longer valid,
261  * since it was either deleted (so the deferred check should be skipped)
262  * or updated (in which case only the latest version of the row should be
263  * checked). Test its liveness according to SnapshotSelf. We need pin
264  * and lock on the buffer to call HeapTupleSatisfiesVisibility. Caller
265  * should be holding pin, but not lock.
266  */
267  if (!table_tuple_satisfies_snapshot(trigdata->tg_relation, newslot, SnapshotSelf))
268  return PointerGetDatum(NULL);
269 
270  /*
271  * Get the relation descriptors of the FK and PK tables.
272  *
273  * pk_rel is opened in RowShareLock mode since that's what our eventual
274  * SELECT FOR KEY SHARE will get on it.
275  */
276  fk_rel = trigdata->tg_relation;
277  pk_rel = table_open(riinfo->pk_relid, RowShareLock);
278 
279  switch (ri_NullCheck(RelationGetDescr(fk_rel), newslot, riinfo, false))
280  {
281  case RI_KEYS_ALL_NULL:
282 
283  /*
284  * No further check needed - an all-NULL key passes every type of
285  * foreign key constraint.
286  */
287  table_close(pk_rel, RowShareLock);
288  return PointerGetDatum(NULL);
289 
290  case RI_KEYS_SOME_NULL:
291 
292  /*
293  * This is the only case that differs between the three kinds of
294  * MATCH.
295  */
296  switch (riinfo->confmatchtype)
297  {
298  case FKCONSTR_MATCH_FULL:
299 
300  /*
301  * Not allowed - MATCH FULL says either all or none of the
302  * attributes can be NULLs
303  */
304  ereport(ERROR,
305  (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
306  errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
307  RelationGetRelationName(fk_rel),
308  NameStr(riinfo->conname)),
309  errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
310  errtableconstraint(fk_rel,
311  NameStr(riinfo->conname))));
312  table_close(pk_rel, RowShareLock);
313  return PointerGetDatum(NULL);
314 
316 
317  /*
318  * MATCH SIMPLE - if ANY column is null, the key passes
319  * the constraint.
320  */
321  table_close(pk_rel, RowShareLock);
322  return PointerGetDatum(NULL);
323 
324 #ifdef NOT_USED
326 
327  /*
328  * MATCH PARTIAL - all non-null columns must match. (not
329  * implemented, can be done by modifying the query below
330  * to only include non-null columns, or by writing a
331  * special version here)
332  */
333  break;
334 #endif
335  }
336 
337  case RI_KEYS_NONE_NULL:
338 
339  /*
340  * Have a full qualified key - continue below for all three kinds
341  * of MATCH.
342  */
343  break;
344  }
345 
346  if (SPI_connect() != SPI_OK_CONNECT)
347  elog(ERROR, "SPI_connect failed");
348 
349  /* Fetch or prepare a saved plan for the real check */
351 
352  if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
353  {
354  StringInfoData querybuf;
355  char pkrelname[MAX_QUOTED_REL_NAME_LEN];
357  char paramname[16];
358  const char *querysep;
359  Oid queryoids[RI_MAX_NUMKEYS];
360  const char *pk_only;
361 
362  /* ----------
363  * The query string built is
364  * SELECT 1 FROM [ONLY] <pktable> x WHERE pkatt1 = $1 [AND ...]
365  * FOR KEY SHARE OF x
366  * The type id's for the $ parameters are those of the
367  * corresponding FK attributes.
368  * ----------
369  */
370  initStringInfo(&querybuf);
371  pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
372  "" : "ONLY ";
373  quoteRelationName(pkrelname, pk_rel);
374  appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
375  pk_only, pkrelname);
376  querysep = "WHERE";
377  for (int i = 0; i < riinfo->nkeys; i++)
378  {
379  Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
380  Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
381 
383  RIAttName(pk_rel, riinfo->pk_attnums[i]));
384  sprintf(paramname, "$%d", i + 1);
385  ri_GenerateQual(&querybuf, querysep,
386  attname, pk_type,
387  riinfo->pf_eq_oprs[i],
388  paramname, fk_type);
389  querysep = "AND";
390  queryoids[i] = fk_type;
391  }
392  appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
393 
394  /* Prepare and save the plan */
395  qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
396  &qkey, fk_rel, pk_rel);
397  }
398 
399  /*
400  * Now check that foreign key exists in PK table
401  *
402  * XXX detectNewRows must be true when a partitioned table is on the
403  * referenced side. The reason is that our snapshot must be fresh in
404  * order for the hack in find_inheritance_children() to work.
405  */
406  ri_PerformCheck(riinfo, &qkey, qplan,
407  fk_rel, pk_rel,
408  NULL, newslot,
409  pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE,
410  SPI_OK_SELECT);
411 
412  if (SPI_finish() != SPI_OK_FINISH)
413  elog(ERROR, "SPI_finish failed");
414 
415  table_close(pk_rel, RowShareLock);
416 
417  return PointerGetDatum(NULL);
418 }
419 
420 
421 /*
422  * RI_FKey_check_ins -
423  *
424  * Check foreign key existence at insert event on FK table.
425  */
426 Datum
428 {
429  /* Check that this is a valid trigger call on the right time and event. */
430  ri_CheckTrigger(fcinfo, "RI_FKey_check_ins", RI_TRIGTYPE_INSERT);
431 
432  /* Share code with UPDATE case. */
433  return RI_FKey_check((TriggerData *) fcinfo->context);
434 }
435 
436 
437 /*
438  * RI_FKey_check_upd -
439  *
440  * Check foreign key existence at update event on FK table.
441  */
442 Datum
444 {
445  /* Check that this is a valid trigger call on the right time and event. */
446  ri_CheckTrigger(fcinfo, "RI_FKey_check_upd", RI_TRIGTYPE_UPDATE);
447 
448  /* Share code with INSERT case. */
449  return RI_FKey_check((TriggerData *) fcinfo->context);
450 }
451 
452 
453 /*
454  * ri_Check_Pk_Match
455  *
456  * Check to see if another PK row has been created that provides the same
457  * key values as the "oldslot" that's been modified or deleted in our trigger
458  * event. Returns true if a match is found in the PK table.
459  *
460  * We assume the caller checked that the oldslot contains no NULL key values,
461  * since otherwise a match is impossible.
462  */
463 static bool
465  TupleTableSlot *oldslot,
466  const RI_ConstraintInfo *riinfo)
467 {
468  SPIPlanPtr qplan;
469  RI_QueryKey qkey;
470  bool result;
471 
472  /* Only called for non-null rows */
473  Assert(ri_NullCheck(RelationGetDescr(pk_rel), oldslot, riinfo, true) == RI_KEYS_NONE_NULL);
474 
475  if (SPI_connect() != SPI_OK_CONNECT)
476  elog(ERROR, "SPI_connect failed");
477 
478  /*
479  * Fetch or prepare a saved plan for checking PK table with values coming
480  * from a PK row
481  */
483 
484  if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
485  {
486  StringInfoData querybuf;
487  char pkrelname[MAX_QUOTED_REL_NAME_LEN];
489  char paramname[16];
490  const char *querysep;
491  const char *pk_only;
492  Oid queryoids[RI_MAX_NUMKEYS];
493 
494  /* ----------
495  * The query string built is
496  * SELECT 1 FROM [ONLY] <pktable> x WHERE pkatt1 = $1 [AND ...]
497  * FOR KEY SHARE OF x
498  * The type id's for the $ parameters are those of the
499  * PK attributes themselves.
500  * ----------
501  */
502  initStringInfo(&querybuf);
503  pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
504  "" : "ONLY ";
505  quoteRelationName(pkrelname, pk_rel);
506  appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
507  pk_only, pkrelname);
508  querysep = "WHERE";
509  for (int i = 0; i < riinfo->nkeys; i++)
510  {
511  Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
512 
514  RIAttName(pk_rel, riinfo->pk_attnums[i]));
515  sprintf(paramname, "$%d", i + 1);
516  ri_GenerateQual(&querybuf, querysep,
517  attname, pk_type,
518  riinfo->pp_eq_oprs[i],
519  paramname, pk_type);
520  querysep = "AND";
521  queryoids[i] = pk_type;
522  }
523  appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
524 
525  /* Prepare and save the plan */
526  qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
527  &qkey, fk_rel, pk_rel);
528  }
529 
530  /*
531  * We have a plan now. Run it.
532  */
533  result = ri_PerformCheck(riinfo, &qkey, qplan,
534  fk_rel, pk_rel,
535  oldslot, NULL,
536  true, /* treat like update */
537  SPI_OK_SELECT);
538 
539  if (SPI_finish() != SPI_OK_FINISH)
540  elog(ERROR, "SPI_finish failed");
541 
542  return result;
543 }
544 
545 
546 /*
547  * RI_FKey_noaction_del -
548  *
549  * Give an error and roll back the current transaction if the
550  * delete has resulted in a violation of the given referential
551  * integrity constraint.
552  */
553 Datum
555 {
556  /* Check that this is a valid trigger call on the right time and event. */
557  ri_CheckTrigger(fcinfo, "RI_FKey_noaction_del", RI_TRIGTYPE_DELETE);
558 
559  /* Share code with RESTRICT/UPDATE cases. */
560  return ri_restrict((TriggerData *) fcinfo->context, true);
561 }
562 
563 /*
564  * RI_FKey_restrict_del -
565  *
566  * Restrict delete from PK table to rows unreferenced by foreign key.
567  *
568  * The SQL standard intends that this referential action occur exactly when
569  * the delete is performed, rather than after. This appears to be
570  * the only difference between "NO ACTION" and "RESTRICT". In Postgres
571  * we still implement this as an AFTER trigger, but it's non-deferrable.
572  */
573 Datum
575 {
576  /* Check that this is a valid trigger call on the right time and event. */
577  ri_CheckTrigger(fcinfo, "RI_FKey_restrict_del", RI_TRIGTYPE_DELETE);
578 
579  /* Share code with NO ACTION/UPDATE cases. */
580  return ri_restrict((TriggerData *) fcinfo->context, false);
581 }
582 
583 /*
584  * RI_FKey_noaction_upd -
585  *
586  * Give an error and roll back the current transaction if the
587  * update has resulted in a violation of the given referential
588  * integrity constraint.
589  */
590 Datum
592 {
593  /* Check that this is a valid trigger call on the right time and event. */
594  ri_CheckTrigger(fcinfo, "RI_FKey_noaction_upd", RI_TRIGTYPE_UPDATE);
595 
596  /* Share code with RESTRICT/DELETE cases. */
597  return ri_restrict((TriggerData *) fcinfo->context, true);
598 }
599 
600 /*
601  * RI_FKey_restrict_upd -
602  *
603  * Restrict update of PK to rows unreferenced by foreign key.
604  *
605  * The SQL standard intends that this referential action occur exactly when
606  * the update is performed, rather than after. This appears to be
607  * the only difference between "NO ACTION" and "RESTRICT". In Postgres
608  * we still implement this as an AFTER trigger, but it's non-deferrable.
609  */
610 Datum
612 {
613  /* Check that this is a valid trigger call on the right time and event. */
614  ri_CheckTrigger(fcinfo, "RI_FKey_restrict_upd", RI_TRIGTYPE_UPDATE);
615 
616  /* Share code with NO ACTION/DELETE cases. */
617  return ri_restrict((TriggerData *) fcinfo->context, false);
618 }
619 
620 /*
621  * ri_restrict -
622  *
623  * Common code for ON DELETE RESTRICT, ON DELETE NO ACTION,
624  * ON UPDATE RESTRICT, and ON UPDATE NO ACTION.
625  */
626 static Datum
627 ri_restrict(TriggerData *trigdata, bool is_no_action)
628 {
629  const RI_ConstraintInfo *riinfo;
630  Relation fk_rel;
631  Relation pk_rel;
632  TupleTableSlot *oldslot;
633  RI_QueryKey qkey;
634  SPIPlanPtr qplan;
635 
636  riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
637  trigdata->tg_relation, true);
638 
639  /*
640  * Get the relation descriptors of the FK and PK tables and the old tuple.
641  *
642  * fk_rel is opened in RowShareLock mode since that's what our eventual
643  * SELECT FOR KEY SHARE will get on it.
644  */
645  fk_rel = table_open(riinfo->fk_relid, RowShareLock);
646  pk_rel = trigdata->tg_relation;
647  oldslot = trigdata->tg_trigslot;
648 
649  /*
650  * If another PK row now exists providing the old key values, we should
651  * not do anything. However, this check should only be made in the NO
652  * ACTION case; in RESTRICT cases we don't wish to allow another row to be
653  * substituted.
654  */
655  if (is_no_action &&
656  ri_Check_Pk_Match(pk_rel, fk_rel, oldslot, riinfo))
657  {
658  table_close(fk_rel, RowShareLock);
659  return PointerGetDatum(NULL);
660  }
661 
662  if (SPI_connect() != SPI_OK_CONNECT)
663  elog(ERROR, "SPI_connect failed");
664 
665  /*
666  * Fetch or prepare a saved plan for the restrict lookup (it's the same
667  * query for delete and update cases)
668  */
669  ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_RESTRICT);
670 
671  if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
672  {
673  StringInfoData querybuf;
674  char fkrelname[MAX_QUOTED_REL_NAME_LEN];
676  char paramname[16];
677  const char *querysep;
678  Oid queryoids[RI_MAX_NUMKEYS];
679  const char *fk_only;
680 
681  /* ----------
682  * The query string built is
683  * SELECT 1 FROM [ONLY] <fktable> x WHERE $1 = fkatt1 [AND ...]
684  * FOR KEY SHARE OF x
685  * The type id's for the $ parameters are those of the
686  * corresponding PK attributes.
687  * ----------
688  */
689  initStringInfo(&querybuf);
690  fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
691  "" : "ONLY ";
692  quoteRelationName(fkrelname, fk_rel);
693  appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
694  fk_only, fkrelname);
695  querysep = "WHERE";
696  for (int i = 0; i < riinfo->nkeys; i++)
697  {
698  Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
699  Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
700  Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
701  Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
702 
704  RIAttName(fk_rel, riinfo->fk_attnums[i]));
705  sprintf(paramname, "$%d", i + 1);
706  ri_GenerateQual(&querybuf, querysep,
707  paramname, pk_type,
708  riinfo->pf_eq_oprs[i],
709  attname, fk_type);
710  if (pk_coll != fk_coll && !get_collation_isdeterministic(pk_coll))
711  ri_GenerateQualCollation(&querybuf, pk_coll);
712  querysep = "AND";
713  queryoids[i] = pk_type;
714  }
715  appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
716 
717  /* Prepare and save the plan */
718  qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
719  &qkey, fk_rel, pk_rel);
720  }
721 
722  /*
723  * We have a plan now. Run it to check for existing references.
724  */
725  ri_PerformCheck(riinfo, &qkey, qplan,
726  fk_rel, pk_rel,
727  oldslot, NULL,
728  true, /* must detect new rows */
729  SPI_OK_SELECT);
730 
731  if (SPI_finish() != SPI_OK_FINISH)
732  elog(ERROR, "SPI_finish failed");
733 
734  table_close(fk_rel, RowShareLock);
735 
736  return PointerGetDatum(NULL);
737 }
738 
739 
740 /*
741  * RI_FKey_cascade_del -
742  *
743  * Cascaded delete foreign key references at delete event on PK table.
744  */
745 Datum
747 {
748  TriggerData *trigdata = (TriggerData *) fcinfo->context;
749  const RI_ConstraintInfo *riinfo;
750  Relation fk_rel;
751  Relation pk_rel;
752  TupleTableSlot *oldslot;
753  RI_QueryKey qkey;
754  SPIPlanPtr qplan;
755 
756  /* Check that this is a valid trigger call on the right time and event. */
757  ri_CheckTrigger(fcinfo, "RI_FKey_cascade_del", RI_TRIGTYPE_DELETE);
758 
759  riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
760  trigdata->tg_relation, true);
761 
762  /*
763  * Get the relation descriptors of the FK and PK tables and the old tuple.
764  *
765  * fk_rel is opened in RowExclusiveLock mode since that's what our
766  * eventual DELETE will get on it.
767  */
768  fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
769  pk_rel = trigdata->tg_relation;
770  oldslot = trigdata->tg_trigslot;
771 
772  if (SPI_connect() != SPI_OK_CONNECT)
773  elog(ERROR, "SPI_connect failed");
774 
775  /* Fetch or prepare a saved plan for the cascaded delete */
777 
778  if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
779  {
780  StringInfoData querybuf;
781  char fkrelname[MAX_QUOTED_REL_NAME_LEN];
783  char paramname[16];
784  const char *querysep;
785  Oid queryoids[RI_MAX_NUMKEYS];
786  const char *fk_only;
787 
788  /* ----------
789  * The query string built is
790  * DELETE FROM [ONLY] <fktable> WHERE $1 = fkatt1 [AND ...]
791  * The type id's for the $ parameters are those of the
792  * corresponding PK attributes.
793  * ----------
794  */
795  initStringInfo(&querybuf);
796  fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
797  "" : "ONLY ";
798  quoteRelationName(fkrelname, fk_rel);
799  appendStringInfo(&querybuf, "DELETE FROM %s%s",
800  fk_only, fkrelname);
801  querysep = "WHERE";
802  for (int i = 0; i < riinfo->nkeys; i++)
803  {
804  Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
805  Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
806  Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
807  Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
808 
810  RIAttName(fk_rel, riinfo->fk_attnums[i]));
811  sprintf(paramname, "$%d", i + 1);
812  ri_GenerateQual(&querybuf, querysep,
813  paramname, pk_type,
814  riinfo->pf_eq_oprs[i],
815  attname, fk_type);
816  if (pk_coll != fk_coll && !get_collation_isdeterministic(pk_coll))
817  ri_GenerateQualCollation(&querybuf, pk_coll);
818  querysep = "AND";
819  queryoids[i] = pk_type;
820  }
821 
822  /* Prepare and save the plan */
823  qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
824  &qkey, fk_rel, pk_rel);
825  }
826 
827  /*
828  * We have a plan now. Build up the arguments from the key values in the
829  * deleted PK tuple and delete the referencing rows
830  */
831  ri_PerformCheck(riinfo, &qkey, qplan,
832  fk_rel, pk_rel,
833  oldslot, NULL,
834  true, /* must detect new rows */
835  SPI_OK_DELETE);
836 
837  if (SPI_finish() != SPI_OK_FINISH)
838  elog(ERROR, "SPI_finish failed");
839 
840  table_close(fk_rel, RowExclusiveLock);
841 
842  return PointerGetDatum(NULL);
843 }
844 
845 
846 /*
847  * RI_FKey_cascade_upd -
848  *
849  * Cascaded update foreign key references at update event on PK table.
850  */
851 Datum
853 {
854  TriggerData *trigdata = (TriggerData *) fcinfo->context;
855  const RI_ConstraintInfo *riinfo;
856  Relation fk_rel;
857  Relation pk_rel;
858  TupleTableSlot *newslot;
859  TupleTableSlot *oldslot;
860  RI_QueryKey qkey;
861  SPIPlanPtr qplan;
862 
863  /* Check that this is a valid trigger call on the right time and event. */
864  ri_CheckTrigger(fcinfo, "RI_FKey_cascade_upd", RI_TRIGTYPE_UPDATE);
865 
866  riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
867  trigdata->tg_relation, true);
868 
869  /*
870  * Get the relation descriptors of the FK and PK tables and the new and
871  * old tuple.
872  *
873  * fk_rel is opened in RowExclusiveLock mode since that's what our
874  * eventual UPDATE will get on it.
875  */
876  fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
877  pk_rel = trigdata->tg_relation;
878  newslot = trigdata->tg_newslot;
879  oldslot = trigdata->tg_trigslot;
880 
881  if (SPI_connect() != SPI_OK_CONNECT)
882  elog(ERROR, "SPI_connect failed");
883 
884  /* Fetch or prepare a saved plan for the cascaded update */
886 
887  if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
888  {
889  StringInfoData querybuf;
890  StringInfoData qualbuf;
891  char fkrelname[MAX_QUOTED_REL_NAME_LEN];
893  char paramname[16];
894  const char *querysep;
895  const char *qualsep;
896  Oid queryoids[RI_MAX_NUMKEYS * 2];
897  const char *fk_only;
898 
899  /* ----------
900  * The query string built is
901  * UPDATE [ONLY] <fktable> SET fkatt1 = $1 [, ...]
902  * WHERE $n = fkatt1 [AND ...]
903  * The type id's for the $ parameters are those of the
904  * corresponding PK attributes. Note that we are assuming
905  * there is an assignment cast from the PK to the FK type;
906  * else the parser will fail.
907  * ----------
908  */
909  initStringInfo(&querybuf);
910  initStringInfo(&qualbuf);
911  fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
912  "" : "ONLY ";
913  quoteRelationName(fkrelname, fk_rel);
914  appendStringInfo(&querybuf, "UPDATE %s%s SET",
915  fk_only, fkrelname);
916  querysep = "";
917  qualsep = "WHERE";
918  for (int i = 0, j = riinfo->nkeys; i < riinfo->nkeys; i++, j++)
919  {
920  Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
921  Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
922  Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
923  Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
924 
926  RIAttName(fk_rel, riinfo->fk_attnums[i]));
927  appendStringInfo(&querybuf,
928  "%s %s = $%d",
929  querysep, attname, i + 1);
930  sprintf(paramname, "$%d", j + 1);
931  ri_GenerateQual(&qualbuf, qualsep,
932  paramname, pk_type,
933  riinfo->pf_eq_oprs[i],
934  attname, fk_type);
935  if (pk_coll != fk_coll && !get_collation_isdeterministic(pk_coll))
936  ri_GenerateQualCollation(&querybuf, pk_coll);
937  querysep = ",";
938  qualsep = "AND";
939  queryoids[i] = pk_type;
940  queryoids[j] = pk_type;
941  }
942  appendBinaryStringInfo(&querybuf, qualbuf.data, qualbuf.len);
943 
944  /* Prepare and save the plan */
945  qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys * 2, queryoids,
946  &qkey, fk_rel, pk_rel);
947  }
948 
949  /*
950  * We have a plan now. Run it to update the existing references.
951  */
952  ri_PerformCheck(riinfo, &qkey, qplan,
953  fk_rel, pk_rel,
954  oldslot, newslot,
955  true, /* must detect new rows */
956  SPI_OK_UPDATE);
957 
958  if (SPI_finish() != SPI_OK_FINISH)
959  elog(ERROR, "SPI_finish failed");
960 
961  table_close(fk_rel, RowExclusiveLock);
962 
963  return PointerGetDatum(NULL);
964 }
965 
966 
967 /*
968  * RI_FKey_setnull_del -
969  *
970  * Set foreign key references to NULL values at delete event on PK table.
971  */
972 Datum
974 {
975  /* Check that this is a valid trigger call on the right time and event. */
976  ri_CheckTrigger(fcinfo, "RI_FKey_setnull_del", RI_TRIGTYPE_DELETE);
977 
978  /* Share code with UPDATE case */
979  return ri_set((TriggerData *) fcinfo->context, true, RI_TRIGTYPE_DELETE);
980 }
981 
982 /*
983  * RI_FKey_setnull_upd -
984  *
985  * Set foreign key references to NULL at update event on PK table.
986  */
987 Datum
989 {
990  /* Check that this is a valid trigger call on the right time and event. */
991  ri_CheckTrigger(fcinfo, "RI_FKey_setnull_upd", RI_TRIGTYPE_UPDATE);
992 
993  /* Share code with DELETE case */
994  return ri_set((TriggerData *) fcinfo->context, true, RI_TRIGTYPE_UPDATE);
995 }
996 
997 /*
998  * RI_FKey_setdefault_del -
999  *
1000  * Set foreign key references to defaults at delete event on PK table.
1001  */
1002 Datum
1004 {
1005  /* Check that this is a valid trigger call on the right time and event. */
1006  ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_del", RI_TRIGTYPE_DELETE);
1007 
1008  /* Share code with UPDATE case */
1009  return ri_set((TriggerData *) fcinfo->context, false, RI_TRIGTYPE_DELETE);
1010 }
1011 
1012 /*
1013  * RI_FKey_setdefault_upd -
1014  *
1015  * Set foreign key references to defaults at update event on PK table.
1016  */
1017 Datum
1019 {
1020  /* Check that this is a valid trigger call on the right time and event. */
1021  ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_upd", RI_TRIGTYPE_UPDATE);
1022 
1023  /* Share code with DELETE case */
1024  return ri_set((TriggerData *) fcinfo->context, false, RI_TRIGTYPE_UPDATE);
1025 }
1026 
1027 /*
1028  * ri_set -
1029  *
1030  * Common code for ON DELETE SET NULL, ON DELETE SET DEFAULT, ON UPDATE SET
1031  * NULL, and ON UPDATE SET DEFAULT.
1032  */
1033 static Datum
1034 ri_set(TriggerData *trigdata, bool is_set_null, int tgkind)
1035 {
1036  const RI_ConstraintInfo *riinfo;
1037  Relation fk_rel;
1038  Relation pk_rel;
1039  TupleTableSlot *oldslot;
1040  RI_QueryKey qkey;
1041  SPIPlanPtr qplan;
1042  int32 queryno;
1043 
1044  riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
1045  trigdata->tg_relation, true);
1046 
1047  /*
1048  * Get the relation descriptors of the FK and PK tables and the old tuple.
1049  *
1050  * fk_rel is opened in RowExclusiveLock mode since that's what our
1051  * eventual UPDATE will get on it.
1052  */
1053  fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
1054  pk_rel = trigdata->tg_relation;
1055  oldslot = trigdata->tg_trigslot;
1056 
1057  if (SPI_connect() != SPI_OK_CONNECT)
1058  elog(ERROR, "SPI_connect failed");
1059 
1060  /*
1061  * Fetch or prepare a saved plan for the trigger.
1062  */
1063  switch (tgkind)
1064  {
1065  case RI_TRIGTYPE_UPDATE:
1066  queryno = is_set_null
1069  break;
1070  case RI_TRIGTYPE_DELETE:
1071  queryno = is_set_null
1074  break;
1075  default:
1076  elog(ERROR, "invalid tgkind passed to ri_set");
1077  }
1078 
1079  ri_BuildQueryKey(&qkey, riinfo, queryno);
1080 
1081  if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
1082  {
1083  StringInfoData querybuf;
1084  char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1086  char paramname[16];
1087  const char *querysep;
1088  const char *qualsep;
1089  Oid queryoids[RI_MAX_NUMKEYS];
1090  const char *fk_only;
1091  int num_cols_to_set;
1092  const int16 *set_cols;
1093 
1094  switch (tgkind)
1095  {
1096  case RI_TRIGTYPE_UPDATE:
1097  num_cols_to_set = riinfo->nkeys;
1098  set_cols = riinfo->fk_attnums;
1099  break;
1100  case RI_TRIGTYPE_DELETE:
1101 
1102  /*
1103  * If confdelsetcols are present, then we only update the
1104  * columns specified in that array, otherwise we update all
1105  * the referencing columns.
1106  */
1107  if (riinfo->ndelsetcols != 0)
1108  {
1109  num_cols_to_set = riinfo->ndelsetcols;
1110  set_cols = riinfo->confdelsetcols;
1111  }
1112  else
1113  {
1114  num_cols_to_set = riinfo->nkeys;
1115  set_cols = riinfo->fk_attnums;
1116  }
1117  break;
1118  default:
1119  elog(ERROR, "invalid tgkind passed to ri_set");
1120  }
1121 
1122  /* ----------
1123  * The query string built is
1124  * UPDATE [ONLY] <fktable> SET fkatt1 = {NULL|DEFAULT} [, ...]
1125  * WHERE $1 = fkatt1 [AND ...]
1126  * The type id's for the $ parameters are those of the
1127  * corresponding PK attributes.
1128  * ----------
1129  */
1130  initStringInfo(&querybuf);
1131  fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1132  "" : "ONLY ";
1133  quoteRelationName(fkrelname, fk_rel);
1134  appendStringInfo(&querybuf, "UPDATE %s%s SET",
1135  fk_only, fkrelname);
1136 
1137  /*
1138  * Add assignment clauses
1139  */
1140  querysep = "";
1141  for (int i = 0; i < num_cols_to_set; i++)
1142  {
1143  quoteOneName(attname, RIAttName(fk_rel, set_cols[i]));
1144  appendStringInfo(&querybuf,
1145  "%s %s = %s",
1146  querysep, attname,
1147  is_set_null ? "NULL" : "DEFAULT");
1148  querysep = ",";
1149  }
1150 
1151  /*
1152  * Add WHERE clause
1153  */
1154  qualsep = "WHERE";
1155  for (int i = 0; i < riinfo->nkeys; i++)
1156  {
1157  Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1158  Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1159  Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
1160  Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
1161 
1163  RIAttName(fk_rel, riinfo->fk_attnums[i]));
1164 
1165  sprintf(paramname, "$%d", i + 1);
1166  ri_GenerateQual(&querybuf, qualsep,
1167  paramname, pk_type,
1168  riinfo->pf_eq_oprs[i],
1169  attname, fk_type);
1170  if (pk_coll != fk_coll && !get_collation_isdeterministic(pk_coll))
1171  ri_GenerateQualCollation(&querybuf, pk_coll);
1172  qualsep = "AND";
1173  queryoids[i] = pk_type;
1174  }
1175 
1176  /* Prepare and save the plan */
1177  qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
1178  &qkey, fk_rel, pk_rel);
1179  }
1180 
1181  /*
1182  * We have a plan now. Run it to update the existing references.
1183  */
1184  ri_PerformCheck(riinfo, &qkey, qplan,
1185  fk_rel, pk_rel,
1186  oldslot, NULL,
1187  true, /* must detect new rows */
1188  SPI_OK_UPDATE);
1189 
1190  if (SPI_finish() != SPI_OK_FINISH)
1191  elog(ERROR, "SPI_finish failed");
1192 
1193  table_close(fk_rel, RowExclusiveLock);
1194 
1195  if (is_set_null)
1196  return PointerGetDatum(NULL);
1197  else
1198  {
1199  /*
1200  * If we just deleted or updated the PK row whose key was equal to the
1201  * FK columns' default values, and a referencing row exists in the FK
1202  * table, we would have updated that row to the same values it already
1203  * had --- and RI_FKey_fk_upd_check_required would hence believe no
1204  * check is necessary. So we need to do another lookup now and in
1205  * case a reference still exists, abort the operation. That is
1206  * already implemented in the NO ACTION trigger, so just run it. (This
1207  * recheck is only needed in the SET DEFAULT case, since CASCADE would
1208  * remove such rows in case of a DELETE operation or would change the
1209  * FK key values in case of an UPDATE, while SET NULL is certain to
1210  * result in rows that satisfy the FK constraint.)
1211  */
1212  return ri_restrict(trigdata, true);
1213  }
1214 }
1215 
1216 
1217 /*
1218  * RI_FKey_pk_upd_check_required -
1219  *
1220  * Check if we really need to fire the RI trigger for an update or delete to a PK
1221  * relation. This is called by the AFTER trigger queue manager to see if
1222  * it can skip queuing an instance of an RI trigger. Returns true if the
1223  * trigger must be fired, false if we can prove the constraint will still
1224  * be satisfied.
1225  *
1226  * newslot will be NULL if this is called for a delete.
1227  */
1228 bool
1230  TupleTableSlot *oldslot, TupleTableSlot *newslot)
1231 {
1232  const RI_ConstraintInfo *riinfo;
1233 
1234  riinfo = ri_FetchConstraintInfo(trigger, pk_rel, true);
1235 
1236  /*
1237  * If any old key value is NULL, the row could not have been referenced by
1238  * an FK row, so no check is needed.
1239  */
1240  if (ri_NullCheck(RelationGetDescr(pk_rel), oldslot, riinfo, true) != RI_KEYS_NONE_NULL)
1241  return false;
1242 
1243  /* If all old and new key values are equal, no check is needed */
1244  if (newslot && ri_KeysEqual(pk_rel, oldslot, newslot, riinfo, true))
1245  return false;
1246 
1247  /* Else we need to fire the trigger. */
1248  return true;
1249 }
1250 
1251 /*
1252  * RI_FKey_fk_upd_check_required -
1253  *
1254  * Check if we really need to fire the RI trigger for an update to an FK
1255  * relation. This is called by the AFTER trigger queue manager to see if
1256  * it can skip queuing an instance of an RI trigger. Returns true if the
1257  * trigger must be fired, false if we can prove the constraint will still
1258  * be satisfied.
1259  */
1260 bool
1262  TupleTableSlot *oldslot, TupleTableSlot *newslot)
1263 {
1264  const RI_ConstraintInfo *riinfo;
1265  int ri_nullcheck;
1266  Datum xminDatum;
1267  TransactionId xmin;
1268  bool isnull;
1269 
1270  /*
1271  * AfterTriggerSaveEvent() handles things such that this function is never
1272  * called for partitioned tables.
1273  */
1274  Assert(fk_rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE);
1275 
1276  riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1277 
1278  ri_nullcheck = ri_NullCheck(RelationGetDescr(fk_rel), newslot, riinfo, false);
1279 
1280  /*
1281  * If all new key values are NULL, the row satisfies the constraint, so no
1282  * check is needed.
1283  */
1284  if (ri_nullcheck == RI_KEYS_ALL_NULL)
1285  return false;
1286 
1287  /*
1288  * If some new key values are NULL, the behavior depends on the match
1289  * type.
1290  */
1291  else if (ri_nullcheck == RI_KEYS_SOME_NULL)
1292  {
1293  switch (riinfo->confmatchtype)
1294  {
1295  case FKCONSTR_MATCH_SIMPLE:
1296 
1297  /*
1298  * If any new key value is NULL, the row must satisfy the
1299  * constraint, so no check is needed.
1300  */
1301  return false;
1302 
1304 
1305  /*
1306  * Don't know, must run full check.
1307  */
1308  break;
1309 
1310  case FKCONSTR_MATCH_FULL:
1311 
1312  /*
1313  * If some new key values are NULL, the row fails the
1314  * constraint. We must not throw error here, because the row
1315  * might get invalidated before the constraint is to be
1316  * checked, but we should queue the event to apply the check
1317  * later.
1318  */
1319  return true;
1320  }
1321  }
1322 
1323  /*
1324  * Continues here for no new key values are NULL, or we couldn't decide
1325  * yet.
1326  */
1327 
1328  /*
1329  * If the original row was inserted by our own transaction, we must fire
1330  * the trigger whether or not the keys are equal. This is because our
1331  * UPDATE will invalidate the INSERT so that the INSERT RI trigger will
1332  * not do anything; so we had better do the UPDATE check. (We could skip
1333  * this if we knew the INSERT trigger already fired, but there is no easy
1334  * way to know that.)
1335  */
1336  xminDatum = slot_getsysattr(oldslot, MinTransactionIdAttributeNumber, &isnull);
1337  Assert(!isnull);
1338  xmin = DatumGetTransactionId(xminDatum);
1340  return true;
1341 
1342  /* If all old and new key values are equal, no check is needed */
1343  if (ri_KeysEqual(fk_rel, oldslot, newslot, riinfo, false))
1344  return false;
1345 
1346  /* Else we need to fire the trigger. */
1347  return true;
1348 }
1349 
1350 /*
1351  * RI_Initial_Check -
1352  *
1353  * Check an entire table for non-matching values using a single query.
1354  * This is not a trigger procedure, but is called during ALTER TABLE
1355  * ADD FOREIGN KEY to validate the initial table contents.
1356  *
1357  * We expect that the caller has made provision to prevent any problems
1358  * caused by concurrent actions. This could be either by locking rel and
1359  * pkrel at ShareRowExclusiveLock or higher, or by otherwise ensuring
1360  * that triggers implementing the checks are already active.
1361  * Hence, we do not need to lock individual rows for the check.
1362  *
1363  * If the check fails because the current user doesn't have permissions
1364  * to read both tables, return false to let our caller know that they will
1365  * need to do something else to check the constraint.
1366  */
1367 bool
1368 RI_Initial_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
1369 {
1370  const RI_ConstraintInfo *riinfo;
1371  StringInfoData querybuf;
1372  char pkrelname[MAX_QUOTED_REL_NAME_LEN];
1373  char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1374  char pkattname[MAX_QUOTED_NAME_LEN + 3];
1375  char fkattname[MAX_QUOTED_NAME_LEN + 3];
1376  RangeTblEntry *rte;
1377  RTEPermissionInfo *pk_perminfo;
1378  RTEPermissionInfo *fk_perminfo;
1379  List *rtes = NIL;
1380  List *perminfos = NIL;
1381  const char *sep;
1382  const char *fk_only;
1383  const char *pk_only;
1384  int save_nestlevel;
1385  char workmembuf[32];
1386  int spi_result;
1387  SPIPlanPtr qplan;
1388 
1389  riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1390 
1391  /*
1392  * Check to make sure current user has enough permissions to do the test
1393  * query. (If not, caller can fall back to the trigger method, which
1394  * works because it changes user IDs on the fly.)
1395  *
1396  * XXX are there any other show-stopper conditions to check?
1397  */
1398  pk_perminfo = makeNode(RTEPermissionInfo);
1399  pk_perminfo->relid = RelationGetRelid(pk_rel);
1400  pk_perminfo->requiredPerms = ACL_SELECT;
1401  perminfos = lappend(perminfos, pk_perminfo);
1402  rte = makeNode(RangeTblEntry);
1403  rte->rtekind = RTE_RELATION;
1404  rte->relid = RelationGetRelid(pk_rel);
1405  rte->relkind = pk_rel->rd_rel->relkind;
1407  rte->perminfoindex = list_length(perminfos);
1408  rtes = lappend(rtes, rte);
1409 
1410  fk_perminfo = makeNode(RTEPermissionInfo);
1411  fk_perminfo->relid = RelationGetRelid(fk_rel);
1412  fk_perminfo->requiredPerms = ACL_SELECT;
1413  perminfos = lappend(perminfos, fk_perminfo);
1414  rte = makeNode(RangeTblEntry);
1415  rte->rtekind = RTE_RELATION;
1416  rte->relid = RelationGetRelid(fk_rel);
1417  rte->relkind = fk_rel->rd_rel->relkind;
1419  rte->perminfoindex = list_length(perminfos);
1420  rtes = lappend(rtes, rte);
1421 
1422  for (int i = 0; i < riinfo->nkeys; i++)
1423  {
1424  int attno;
1425 
1426  attno = riinfo->pk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
1427  pk_perminfo->selectedCols = bms_add_member(pk_perminfo->selectedCols, attno);
1428 
1429  attno = riinfo->fk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
1430  fk_perminfo->selectedCols = bms_add_member(fk_perminfo->selectedCols, attno);
1431  }
1432 
1433  if (!ExecCheckPermissions(rtes, perminfos, false))
1434  return false;
1435 
1436  /*
1437  * Also punt if RLS is enabled on either table unless this role has the
1438  * bypassrls right or is the table owner of the table(s) involved which
1439  * have RLS enabled.
1440  */
1442  ((pk_rel->rd_rel->relrowsecurity &&
1443  !object_ownercheck(RelationRelationId, RelationGetRelid(pk_rel),
1444  GetUserId())) ||
1445  (fk_rel->rd_rel->relrowsecurity &&
1446  !object_ownercheck(RelationRelationId, RelationGetRelid(fk_rel),
1447  GetUserId()))))
1448  return false;
1449 
1450  /*----------
1451  * The query string built is:
1452  * SELECT fk.keycols FROM [ONLY] relname fk
1453  * LEFT OUTER JOIN [ONLY] pkrelname pk
1454  * ON (pk.pkkeycol1=fk.keycol1 [AND ...])
1455  * WHERE pk.pkkeycol1 IS NULL AND
1456  * For MATCH SIMPLE:
1457  * (fk.keycol1 IS NOT NULL [AND ...])
1458  * For MATCH FULL:
1459  * (fk.keycol1 IS NOT NULL [OR ...])
1460  *
1461  * We attach COLLATE clauses to the operators when comparing columns
1462  * that have different collations.
1463  *----------
1464  */
1465  initStringInfo(&querybuf);
1466  appendStringInfoString(&querybuf, "SELECT ");
1467  sep = "";
1468  for (int i = 0; i < riinfo->nkeys; i++)
1469  {
1470  quoteOneName(fkattname,
1471  RIAttName(fk_rel, riinfo->fk_attnums[i]));
1472  appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
1473  sep = ", ";
1474  }
1475 
1476  quoteRelationName(pkrelname, pk_rel);
1477  quoteRelationName(fkrelname, fk_rel);
1478  fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1479  "" : "ONLY ";
1480  pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1481  "" : "ONLY ";
1482  appendStringInfo(&querybuf,
1483  " FROM %s%s fk LEFT OUTER JOIN %s%s pk ON",
1484  fk_only, fkrelname, pk_only, pkrelname);
1485 
1486  strcpy(pkattname, "pk.");
1487  strcpy(fkattname, "fk.");
1488  sep = "(";
1489  for (int i = 0; i < riinfo->nkeys; i++)
1490  {
1491  Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1492  Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1493  Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
1494  Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
1495 
1496  quoteOneName(pkattname + 3,
1497  RIAttName(pk_rel, riinfo->pk_attnums[i]));
1498  quoteOneName(fkattname + 3,
1499  RIAttName(fk_rel, riinfo->fk_attnums[i]));
1500  ri_GenerateQual(&querybuf, sep,
1501  pkattname, pk_type,
1502  riinfo->pf_eq_oprs[i],
1503  fkattname, fk_type);
1504  if (pk_coll != fk_coll)
1505  ri_GenerateQualCollation(&querybuf, pk_coll);
1506  sep = "AND";
1507  }
1508 
1509  /*
1510  * It's sufficient to test any one pk attribute for null to detect a join
1511  * failure.
1512  */
1513  quoteOneName(pkattname, RIAttName(pk_rel, riinfo->pk_attnums[0]));
1514  appendStringInfo(&querybuf, ") WHERE pk.%s IS NULL AND (", pkattname);
1515 
1516  sep = "";
1517  for (int i = 0; i < riinfo->nkeys; i++)
1518  {
1519  quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
1520  appendStringInfo(&querybuf,
1521  "%sfk.%s IS NOT NULL",
1522  sep, fkattname);
1523  switch (riinfo->confmatchtype)
1524  {
1525  case FKCONSTR_MATCH_SIMPLE:
1526  sep = " AND ";
1527  break;
1528  case FKCONSTR_MATCH_FULL:
1529  sep = " OR ";
1530  break;
1531  }
1532  }
1533  appendStringInfoChar(&querybuf, ')');
1534 
1535  /*
1536  * Temporarily increase work_mem so that the check query can be executed
1537  * more efficiently. It seems okay to do this because the query is simple
1538  * enough to not use a multiple of work_mem, and one typically would not
1539  * have many large foreign-key validations happening concurrently. So
1540  * this seems to meet the criteria for being considered a "maintenance"
1541  * operation, and accordingly we use maintenance_work_mem. However, we
1542  * must also set hash_mem_multiplier to 1, since it is surely not okay to
1543  * let that get applied to the maintenance_work_mem value.
1544  *
1545  * We use the equivalent of a function SET option to allow the setting to
1546  * persist for exactly the duration of the check query. guc.c also takes
1547  * care of undoing the setting on error.
1548  */
1549  save_nestlevel = NewGUCNestLevel();
1550 
1551  snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
1552  (void) set_config_option("work_mem", workmembuf,
1554  GUC_ACTION_SAVE, true, 0, false);
1555  (void) set_config_option("hash_mem_multiplier", "1",
1557  GUC_ACTION_SAVE, true, 0, false);
1558 
1559  if (SPI_connect() != SPI_OK_CONNECT)
1560  elog(ERROR, "SPI_connect failed");
1561 
1562  /*
1563  * Generate the plan. We don't need to cache it, and there are no
1564  * arguments to the plan.
1565  */
1566  qplan = SPI_prepare(querybuf.data, 0, NULL);
1567 
1568  if (qplan == NULL)
1569  elog(ERROR, "SPI_prepare returned %s for %s",
1571 
1572  /*
1573  * Run the plan. For safety we force a current snapshot to be used. (In
1574  * transaction-snapshot mode, this arguably violates transaction isolation
1575  * rules, but we really haven't got much choice.) We don't need to
1576  * register the snapshot, because SPI_execute_snapshot will see to it. We
1577  * need at most one tuple returned, so pass limit = 1.
1578  */
1579  spi_result = SPI_execute_snapshot(qplan,
1580  NULL, NULL,
1583  true, false, 1);
1584 
1585  /* Check result */
1586  if (spi_result != SPI_OK_SELECT)
1587  elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
1588 
1589  /* Did we find a tuple violating the constraint? */
1590  if (SPI_processed > 0)
1591  {
1592  TupleTableSlot *slot;
1593  HeapTuple tuple = SPI_tuptable->vals[0];
1594  TupleDesc tupdesc = SPI_tuptable->tupdesc;
1595  RI_ConstraintInfo fake_riinfo;
1596 
1597  slot = MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual);
1598 
1599  heap_deform_tuple(tuple, tupdesc,
1600  slot->tts_values, slot->tts_isnull);
1601  ExecStoreVirtualTuple(slot);
1602 
1603  /*
1604  * The columns to look at in the result tuple are 1..N, not whatever
1605  * they are in the fk_rel. Hack up riinfo so that the subroutines
1606  * called here will behave properly.
1607  *
1608  * In addition to this, we have to pass the correct tupdesc to
1609  * ri_ReportViolation, overriding its normal habit of using the pk_rel
1610  * or fk_rel's tupdesc.
1611  */
1612  memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
1613  for (int i = 0; i < fake_riinfo.nkeys; i++)
1614  fake_riinfo.fk_attnums[i] = i + 1;
1615 
1616  /*
1617  * If it's MATCH FULL, and there are any nulls in the FK keys,
1618  * complain about that rather than the lack of a match. MATCH FULL
1619  * disallows partially-null FK rows.
1620  */
1621  if (fake_riinfo.confmatchtype == FKCONSTR_MATCH_FULL &&
1622  ri_NullCheck(tupdesc, slot, &fake_riinfo, false) != RI_KEYS_NONE_NULL)
1623  ereport(ERROR,
1624  (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
1625  errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
1626  RelationGetRelationName(fk_rel),
1627  NameStr(fake_riinfo.conname)),
1628  errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
1629  errtableconstraint(fk_rel,
1630  NameStr(fake_riinfo.conname))));
1631 
1632  /*
1633  * We tell ri_ReportViolation we were doing the RI_PLAN_CHECK_LOOKUPPK
1634  * query, which isn't true, but will cause it to use
1635  * fake_riinfo.fk_attnums as we need.
1636  */
1637  ri_ReportViolation(&fake_riinfo,
1638  pk_rel, fk_rel,
1639  slot, tupdesc,
1640  RI_PLAN_CHECK_LOOKUPPK, false);
1641 
1643  }
1644 
1645  if (SPI_finish() != SPI_OK_FINISH)
1646  elog(ERROR, "SPI_finish failed");
1647 
1648  /*
1649  * Restore work_mem and hash_mem_multiplier.
1650  */
1651  AtEOXact_GUC(true, save_nestlevel);
1652 
1653  return true;
1654 }
1655 
1656 /*
1657  * RI_PartitionRemove_Check -
1658  *
1659  * Verify no referencing values exist, when a partition is detached on
1660  * the referenced side of a foreign key constraint.
1661  */
1662 void
1664 {
1665  const RI_ConstraintInfo *riinfo;
1666  StringInfoData querybuf;
1667  char *constraintDef;
1668  char pkrelname[MAX_QUOTED_REL_NAME_LEN];
1669  char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1670  char pkattname[MAX_QUOTED_NAME_LEN + 3];
1671  char fkattname[MAX_QUOTED_NAME_LEN + 3];
1672  const char *sep;
1673  const char *fk_only;
1674  int save_nestlevel;
1675  char workmembuf[32];
1676  int spi_result;
1677  SPIPlanPtr qplan;
1678  int i;
1679 
1680  riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1681 
1682  /*
1683  * We don't check permissions before displaying the error message, on the
1684  * assumption that the user detaching the partition must have enough
1685  * privileges to examine the table contents anyhow.
1686  */
1687 
1688  /*----------
1689  * The query string built is:
1690  * SELECT fk.keycols FROM [ONLY] relname fk
1691  * JOIN pkrelname pk
1692  * ON (pk.pkkeycol1=fk.keycol1 [AND ...])
1693  * WHERE (<partition constraint>) AND
1694  * For MATCH SIMPLE:
1695  * (fk.keycol1 IS NOT NULL [AND ...])
1696  * For MATCH FULL:
1697  * (fk.keycol1 IS NOT NULL [OR ...])
1698  *
1699  * We attach COLLATE clauses to the operators when comparing columns
1700  * that have different collations.
1701  *----------
1702  */
1703  initStringInfo(&querybuf);
1704  appendStringInfoString(&querybuf, "SELECT ");
1705  sep = "";
1706  for (i = 0; i < riinfo->nkeys; i++)
1707  {
1708  quoteOneName(fkattname,
1709  RIAttName(fk_rel, riinfo->fk_attnums[i]));
1710  appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
1711  sep = ", ";
1712  }
1713 
1714  quoteRelationName(pkrelname, pk_rel);
1715  quoteRelationName(fkrelname, fk_rel);
1716  fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1717  "" : "ONLY ";
1718  appendStringInfo(&querybuf,
1719  " FROM %s%s fk JOIN %s pk ON",
1720  fk_only, fkrelname, pkrelname);
1721  strcpy(pkattname, "pk.");
1722  strcpy(fkattname, "fk.");
1723  sep = "(";
1724  for (i = 0; i < riinfo->nkeys; i++)
1725  {
1726  Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1727  Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1728  Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
1729  Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
1730 
1731  quoteOneName(pkattname + 3,
1732  RIAttName(pk_rel, riinfo->pk_attnums[i]));
1733  quoteOneName(fkattname + 3,
1734  RIAttName(fk_rel, riinfo->fk_attnums[i]));
1735  ri_GenerateQual(&querybuf, sep,
1736  pkattname, pk_type,
1737  riinfo->pf_eq_oprs[i],
1738  fkattname, fk_type);
1739  if (pk_coll != fk_coll)
1740  ri_GenerateQualCollation(&querybuf, pk_coll);
1741  sep = "AND";
1742  }
1743 
1744  /*
1745  * Start the WHERE clause with the partition constraint (except if this is
1746  * the default partition and there's no other partition, because the
1747  * partition constraint is the empty string in that case.)
1748  */
1749  constraintDef = pg_get_partconstrdef_string(RelationGetRelid(pk_rel), "pk");
1750  if (constraintDef && constraintDef[0] != '\0')
1751  appendStringInfo(&querybuf, ") WHERE %s AND (",
1752  constraintDef);
1753  else
1754  appendStringInfoString(&querybuf, ") WHERE (");
1755 
1756  sep = "";
1757  for (i = 0; i < riinfo->nkeys; i++)
1758  {
1759  quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
1760  appendStringInfo(&querybuf,
1761  "%sfk.%s IS NOT NULL",
1762  sep, fkattname);
1763  switch (riinfo->confmatchtype)
1764  {
1765  case FKCONSTR_MATCH_SIMPLE:
1766  sep = " AND ";
1767  break;
1768  case FKCONSTR_MATCH_FULL:
1769  sep = " OR ";
1770  break;
1771  }
1772  }
1773  appendStringInfoChar(&querybuf, ')');
1774 
1775  /*
1776  * Temporarily increase work_mem so that the check query can be executed
1777  * more efficiently. It seems okay to do this because the query is simple
1778  * enough to not use a multiple of work_mem, and one typically would not
1779  * have many large foreign-key validations happening concurrently. So
1780  * this seems to meet the criteria for being considered a "maintenance"
1781  * operation, and accordingly we use maintenance_work_mem. However, we
1782  * must also set hash_mem_multiplier to 1, since it is surely not okay to
1783  * let that get applied to the maintenance_work_mem value.
1784  *
1785  * We use the equivalent of a function SET option to allow the setting to
1786  * persist for exactly the duration of the check query. guc.c also takes
1787  * care of undoing the setting on error.
1788  */
1789  save_nestlevel = NewGUCNestLevel();
1790 
1791  snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
1792  (void) set_config_option("work_mem", workmembuf,
1794  GUC_ACTION_SAVE, true, 0, false);
1795  (void) set_config_option("hash_mem_multiplier", "1",
1797  GUC_ACTION_SAVE, true, 0, false);
1798 
1799  if (SPI_connect() != SPI_OK_CONNECT)
1800  elog(ERROR, "SPI_connect failed");
1801 
1802  /*
1803  * Generate the plan. We don't need to cache it, and there are no
1804  * arguments to the plan.
1805  */
1806  qplan = SPI_prepare(querybuf.data, 0, NULL);
1807 
1808  if (qplan == NULL)
1809  elog(ERROR, "SPI_prepare returned %s for %s",
1811 
1812  /*
1813  * Run the plan. For safety we force a current snapshot to be used. (In
1814  * transaction-snapshot mode, this arguably violates transaction isolation
1815  * rules, but we really haven't got much choice.) We don't need to
1816  * register the snapshot, because SPI_execute_snapshot will see to it. We
1817  * need at most one tuple returned, so pass limit = 1.
1818  */
1819  spi_result = SPI_execute_snapshot(qplan,
1820  NULL, NULL,
1823  true, false, 1);
1824 
1825  /* Check result */
1826  if (spi_result != SPI_OK_SELECT)
1827  elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
1828 
1829  /* Did we find a tuple that would violate the constraint? */
1830  if (SPI_processed > 0)
1831  {
1832  TupleTableSlot *slot;
1833  HeapTuple tuple = SPI_tuptable->vals[0];
1834  TupleDesc tupdesc = SPI_tuptable->tupdesc;
1835  RI_ConstraintInfo fake_riinfo;
1836 
1837  slot = MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual);
1838 
1839  heap_deform_tuple(tuple, tupdesc,
1840  slot->tts_values, slot->tts_isnull);
1841  ExecStoreVirtualTuple(slot);
1842 
1843  /*
1844  * The columns to look at in the result tuple are 1..N, not whatever
1845  * they are in the fk_rel. Hack up riinfo so that ri_ReportViolation
1846  * will behave properly.
1847  *
1848  * In addition to this, we have to pass the correct tupdesc to
1849  * ri_ReportViolation, overriding its normal habit of using the pk_rel
1850  * or fk_rel's tupdesc.
1851  */
1852  memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
1853  for (i = 0; i < fake_riinfo.nkeys; i++)
1854  fake_riinfo.pk_attnums[i] = i + 1;
1855 
1856  ri_ReportViolation(&fake_riinfo, pk_rel, fk_rel,
1857  slot, tupdesc, 0, true);
1858  }
1859 
1860  if (SPI_finish() != SPI_OK_FINISH)
1861  elog(ERROR, "SPI_finish failed");
1862 
1863  /*
1864  * Restore work_mem and hash_mem_multiplier.
1865  */
1866  AtEOXact_GUC(true, save_nestlevel);
1867 }
1868 
1869 
1870 /* ----------
1871  * Local functions below
1872  * ----------
1873  */
1874 
1875 
1876 /*
1877  * quoteOneName --- safely quote a single SQL name
1878  *
1879  * buffer must be MAX_QUOTED_NAME_LEN long (includes room for \0)
1880  */
1881 static void
1882 quoteOneName(char *buffer, const char *name)
1883 {
1884  /* Rather than trying to be smart, just always quote it. */
1885  *buffer++ = '"';
1886  while (*name)
1887  {
1888  if (*name == '"')
1889  *buffer++ = '"';
1890  *buffer++ = *name++;
1891  }
1892  *buffer++ = '"';
1893  *buffer = '\0';
1894 }
1895 
1896 /*
1897  * quoteRelationName --- safely quote a fully qualified relation name
1898  *
1899  * buffer must be MAX_QUOTED_REL_NAME_LEN long (includes room for \0)
1900  */
1901 static void
1902 quoteRelationName(char *buffer, Relation rel)
1903 {
1905  buffer += strlen(buffer);
1906  *buffer++ = '.';
1907  quoteOneName(buffer, RelationGetRelationName(rel));
1908 }
1909 
1910 /*
1911  * ri_GenerateQual --- generate a WHERE clause equating two variables
1912  *
1913  * This basically appends " sep leftop op rightop" to buf, adding casts
1914  * and schema qualification as needed to ensure that the parser will select
1915  * the operator we specify. leftop and rightop should be parenthesized
1916  * if they aren't variables or parameters.
1917  */
1918 static void
1920  const char *sep,
1921  const char *leftop, Oid leftoptype,
1922  Oid opoid,
1923  const char *rightop, Oid rightoptype)
1924 {
1925  appendStringInfo(buf, " %s ", sep);
1926  generate_operator_clause(buf, leftop, leftoptype, opoid,
1927  rightop, rightoptype);
1928 }
1929 
1930 /*
1931  * ri_GenerateQualCollation --- add a COLLATE spec to a WHERE clause
1932  *
1933  * At present, we intentionally do not use this function for RI queries that
1934  * compare a variable to a $n parameter. Since parameter symbols always have
1935  * default collation, the effect will be to use the variable's collation.
1936  * Now that is only strictly correct when testing the referenced column, since
1937  * the SQL standard specifies that RI comparisons should use the referenced
1938  * column's collation. However, so long as all collations have the same
1939  * notion of equality (which they do, because texteq reduces to bitwise
1940  * equality), there's no visible semantic impact from using the referencing
1941  * column's collation when testing it, and this is a good thing to do because
1942  * it lets us use a normal index on the referencing column. However, we do
1943  * have to use this function when directly comparing the referencing and
1944  * referenced columns, if they are of different collations; else the parser
1945  * will fail to resolve the collation to use.
1946  */
1947 static void
1949 {
1950  HeapTuple tp;
1951  Form_pg_collation colltup;
1952  char *collname;
1953  char onename[MAX_QUOTED_NAME_LEN];
1954 
1955  /* Nothing to do if it's a noncollatable data type */
1956  if (!OidIsValid(collation))
1957  return;
1958 
1959  tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(collation));
1960  if (!HeapTupleIsValid(tp))
1961  elog(ERROR, "cache lookup failed for collation %u", collation);
1962  colltup = (Form_pg_collation) GETSTRUCT(tp);
1963  collname = NameStr(colltup->collname);
1964 
1965  /*
1966  * We qualify the name always, for simplicity and to ensure the query is
1967  * not search-path-dependent.
1968  */
1969  quoteOneName(onename, get_namespace_name(colltup->collnamespace));
1970  appendStringInfo(buf, " COLLATE %s", onename);
1971  quoteOneName(onename, collname);
1972  appendStringInfo(buf, ".%s", onename);
1973 
1974  ReleaseSysCache(tp);
1975 }
1976 
1977 /* ----------
1978  * ri_BuildQueryKey -
1979  *
1980  * Construct a hashtable key for a prepared SPI plan of an FK constraint.
1981  *
1982  * key: output argument, *key is filled in based on the other arguments
1983  * riinfo: info derived from pg_constraint entry
1984  * constr_queryno: an internal number identifying the query type
1985  * (see RI_PLAN_XXX constants at head of file)
1986  * ----------
1987  */
1988 static void
1990  int32 constr_queryno)
1991 {
1992  /*
1993  * Inherited constraints with a common ancestor can share ri_query_cache
1994  * entries for all query types except RI_PLAN_CHECK_LOOKUPPK_FROM_PK.
1995  * Except in that case, the query processes the other table involved in
1996  * the FK constraint (i.e., not the table on which the trigger has been
1997  * fired), and so it will be the same for all members of the inheritance
1998  * tree. So we may use the root constraint's OID in the hash key, rather
1999  * than the constraint's own OID. This avoids creating duplicate SPI
2000  * plans, saving lots of work and memory when there are many partitions
2001  * with similar FK constraints.
2002  *
2003  * (Note that we must still have a separate RI_ConstraintInfo for each
2004  * constraint, because partitions can have different column orders,
2005  * resulting in different pk_attnums[] or fk_attnums[] array contents.)
2006  *
2007  * We assume struct RI_QueryKey contains no padding bytes, else we'd need
2008  * to use memset to clear them.
2009  */
2010  if (constr_queryno != RI_PLAN_CHECK_LOOKUPPK_FROM_PK)
2011  key->constr_id = riinfo->constraint_root_id;
2012  else
2013  key->constr_id = riinfo->constraint_id;
2014  key->constr_queryno = constr_queryno;
2015 }
2016 
2017 /*
2018  * Check that RI trigger function was called in expected context
2019  */
2020 static void
2021 ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname, int tgkind)
2022 {
2023  TriggerData *trigdata = (TriggerData *) fcinfo->context;
2024 
2025  if (!CALLED_AS_TRIGGER(fcinfo))
2026  ereport(ERROR,
2027  (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2028  errmsg("function \"%s\" was not called by trigger manager", funcname)));
2029 
2030  /*
2031  * Check proper event
2032  */
2033  if (!TRIGGER_FIRED_AFTER(trigdata->tg_event) ||
2034  !TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
2035  ereport(ERROR,
2036  (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2037  errmsg("function \"%s\" must be fired AFTER ROW", funcname)));
2038 
2039  switch (tgkind)
2040  {
2041  case RI_TRIGTYPE_INSERT:
2042  if (!TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
2043  ereport(ERROR,
2044  (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2045  errmsg("function \"%s\" must be fired for INSERT", funcname)));
2046  break;
2047  case RI_TRIGTYPE_UPDATE:
2048  if (!TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
2049  ereport(ERROR,
2050  (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2051  errmsg("function \"%s\" must be fired for UPDATE", funcname)));
2052  break;
2053  case RI_TRIGTYPE_DELETE:
2054  if (!TRIGGER_FIRED_BY_DELETE(trigdata->tg_event))
2055  ereport(ERROR,
2056  (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2057  errmsg("function \"%s\" must be fired for DELETE", funcname)));
2058  break;
2059  }
2060 }
2061 
2062 
2063 /*
2064  * Fetch the RI_ConstraintInfo struct for the trigger's FK constraint.
2065  */
2066 static const RI_ConstraintInfo *
2067 ri_FetchConstraintInfo(Trigger *trigger, Relation trig_rel, bool rel_is_pk)
2068 {
2069  Oid constraintOid = trigger->tgconstraint;
2070  const RI_ConstraintInfo *riinfo;
2071 
2072  /*
2073  * Check that the FK constraint's OID is available; it might not be if
2074  * we've been invoked via an ordinary trigger or an old-style "constraint
2075  * trigger".
2076  */
2077  if (!OidIsValid(constraintOid))
2078  ereport(ERROR,
2079  (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2080  errmsg("no pg_constraint entry for trigger \"%s\" on table \"%s\"",
2081  trigger->tgname, RelationGetRelationName(trig_rel)),
2082  errhint("Remove this referential integrity trigger and its mates, then do ALTER TABLE ADD CONSTRAINT.")));
2083 
2084  /* Find or create a hashtable entry for the constraint */
2085  riinfo = ri_LoadConstraintInfo(constraintOid);
2086 
2087  /* Do some easy cross-checks against the trigger call data */
2088  if (rel_is_pk)
2089  {
2090  if (riinfo->fk_relid != trigger->tgconstrrelid ||
2091  riinfo->pk_relid != RelationGetRelid(trig_rel))
2092  elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
2093  trigger->tgname, RelationGetRelationName(trig_rel));
2094  }
2095  else
2096  {
2097  if (riinfo->fk_relid != RelationGetRelid(trig_rel) ||
2098  riinfo->pk_relid != trigger->tgconstrrelid)
2099  elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
2100  trigger->tgname, RelationGetRelationName(trig_rel));
2101  }
2102 
2103  if (riinfo->confmatchtype != FKCONSTR_MATCH_FULL &&
2106  elog(ERROR, "unrecognized confmatchtype: %d",
2107  riinfo->confmatchtype);
2108 
2109  if (riinfo->confmatchtype == FKCONSTR_MATCH_PARTIAL)
2110  ereport(ERROR,
2111  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2112  errmsg("MATCH PARTIAL not yet implemented")));
2113 
2114  return riinfo;
2115 }
2116 
2117 /*
2118  * Fetch or create the RI_ConstraintInfo struct for an FK constraint.
2119  */
2120 static const RI_ConstraintInfo *
2122 {
2123  RI_ConstraintInfo *riinfo;
2124  bool found;
2125  HeapTuple tup;
2126  Form_pg_constraint conForm;
2127 
2128  /*
2129  * On the first call initialize the hashtable
2130  */
2131  if (!ri_constraint_cache)
2133 
2134  /*
2135  * Find or create a hash entry. If we find a valid one, just return it.
2136  */
2138  &constraintOid,
2139  HASH_ENTER, &found);
2140  if (!found)
2141  riinfo->valid = false;
2142  else if (riinfo->valid)
2143  return riinfo;
2144 
2145  /*
2146  * Fetch the pg_constraint row so we can fill in the entry.
2147  */
2148  tup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constraintOid));
2149  if (!HeapTupleIsValid(tup)) /* should not happen */
2150  elog(ERROR, "cache lookup failed for constraint %u", constraintOid);
2151  conForm = (Form_pg_constraint) GETSTRUCT(tup);
2152 
2153  if (conForm->contype != CONSTRAINT_FOREIGN) /* should not happen */
2154  elog(ERROR, "constraint %u is not a foreign key constraint",
2155  constraintOid);
2156 
2157  /* And extract data */
2158  Assert(riinfo->constraint_id == constraintOid);
2159  if (OidIsValid(conForm->conparentid))
2160  riinfo->constraint_root_id =
2161  get_ri_constraint_root(conForm->conparentid);
2162  else
2163  riinfo->constraint_root_id = constraintOid;
2165  ObjectIdGetDatum(constraintOid));
2168  memcpy(&riinfo->conname, &conForm->conname, sizeof(NameData));
2169  riinfo->pk_relid = conForm->confrelid;
2170  riinfo->fk_relid = conForm->conrelid;
2171  riinfo->confupdtype = conForm->confupdtype;
2172  riinfo->confdeltype = conForm->confdeltype;
2173  riinfo->confmatchtype = conForm->confmatchtype;
2174 
2176  &riinfo->nkeys,
2177  riinfo->fk_attnums,
2178  riinfo->pk_attnums,
2179  riinfo->pf_eq_oprs,
2180  riinfo->pp_eq_oprs,
2181  riinfo->ff_eq_oprs,
2182  &riinfo->ndelsetcols,
2183  riinfo->confdelsetcols);
2184 
2185  ReleaseSysCache(tup);
2186 
2187  /*
2188  * For efficient processing of invalidation messages below, we keep a
2189  * doubly-linked count list of all currently valid entries.
2190  */
2192 
2193  riinfo->valid = true;
2194 
2195  return riinfo;
2196 }
2197 
2198 /*
2199  * get_ri_constraint_root
2200  * Returns the OID of the constraint's root parent
2201  */
2202 static Oid
2204 {
2205  for (;;)
2206  {
2207  HeapTuple tuple;
2208  Oid constrParentOid;
2209 
2210  tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constrOid));
2211  if (!HeapTupleIsValid(tuple))
2212  elog(ERROR, "cache lookup failed for constraint %u", constrOid);
2213  constrParentOid = ((Form_pg_constraint) GETSTRUCT(tuple))->conparentid;
2214  ReleaseSysCache(tuple);
2215  if (!OidIsValid(constrParentOid))
2216  break; /* we reached the root constraint */
2217  constrOid = constrParentOid;
2218  }
2219  return constrOid;
2220 }
2221 
2222 /*
2223  * Callback for pg_constraint inval events
2224  *
2225  * While most syscache callbacks just flush all their entries, pg_constraint
2226  * gets enough update traffic that it's probably worth being smarter.
2227  * Invalidate any ri_constraint_cache entry associated with the syscache
2228  * entry with the specified hash value, or all entries if hashvalue == 0.
2229  *
2230  * Note: at the time a cache invalidation message is processed there may be
2231  * active references to the cache. Because of this we never remove entries
2232  * from the cache, but only mark them invalid, which is harmless to active
2233  * uses. (Any query using an entry should hold a lock sufficient to keep that
2234  * data from changing under it --- but we may get cache flushes anyway.)
2235  */
2236 static void
2238 {
2239  dlist_mutable_iter iter;
2240 
2241  Assert(ri_constraint_cache != NULL);
2242 
2243  /*
2244  * If the list of currently valid entries gets excessively large, we mark
2245  * them all invalid so we can empty the list. This arrangement avoids
2246  * O(N^2) behavior in situations where a session touches many foreign keys
2247  * and also does many ALTER TABLEs, such as a restore from pg_dump.
2248  */
2250  hashvalue = 0; /* pretend it's a cache reset */
2251 
2253  {
2255  valid_link, iter.cur);
2256 
2257  /*
2258  * We must invalidate not only entries directly matching the given
2259  * hash value, but also child entries, in case the invalidation
2260  * affects a root constraint.
2261  */
2262  if (hashvalue == 0 ||
2263  riinfo->oidHashValue == hashvalue ||
2264  riinfo->rootHashValue == hashvalue)
2265  {
2266  riinfo->valid = false;
2267  /* Remove invalidated entries from the list, too */
2269  }
2270  }
2271 }
2272 
2273 
2274 /*
2275  * Prepare execution plan for a query to enforce an RI restriction
2276  */
2277 static SPIPlanPtr
2278 ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
2279  RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel)
2280 {
2281  SPIPlanPtr qplan;
2282  Relation query_rel;
2283  Oid save_userid;
2284  int save_sec_context;
2285 
2286  /*
2287  * Use the query type code to determine whether the query is run against
2288  * the PK or FK table; we'll do the check as that table's owner
2289  */
2290  if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
2291  query_rel = pk_rel;
2292  else
2293  query_rel = fk_rel;
2294 
2295  /* Switch to proper UID to perform check as */
2296  GetUserIdAndSecContext(&save_userid, &save_sec_context);
2297  SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
2298  save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
2300 
2301  /* Create the plan */
2302  qplan = SPI_prepare(querystr, nargs, argtypes);
2303 
2304  if (qplan == NULL)
2305  elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), querystr);
2306 
2307  /* Restore UID and security context */
2308  SetUserIdAndSecContext(save_userid, save_sec_context);
2309 
2310  /* Save the plan */
2311  SPI_keepplan(qplan);
2312  ri_HashPreparedPlan(qkey, qplan);
2313 
2314  return qplan;
2315 }
2316 
2317 /*
2318  * Perform a query to enforce an RI restriction
2319  */
2320 static bool
2322  RI_QueryKey *qkey, SPIPlanPtr qplan,
2323  Relation fk_rel, Relation pk_rel,
2324  TupleTableSlot *oldslot, TupleTableSlot *newslot,
2325  bool detectNewRows, int expect_OK)
2326 {
2327  Relation query_rel,
2328  source_rel;
2329  bool source_is_pk;
2330  Snapshot test_snapshot;
2331  Snapshot crosscheck_snapshot;
2332  int limit;
2333  int spi_result;
2334  Oid save_userid;
2335  int save_sec_context;
2336  Datum vals[RI_MAX_NUMKEYS * 2];
2337  char nulls[RI_MAX_NUMKEYS * 2];
2338 
2339  /*
2340  * Use the query type code to determine whether the query is run against
2341  * the PK or FK table; we'll do the check as that table's owner
2342  */
2343  if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
2344  query_rel = pk_rel;
2345  else
2346  query_rel = fk_rel;
2347 
2348  /*
2349  * The values for the query are taken from the table on which the trigger
2350  * is called - it is normally the other one with respect to query_rel. An
2351  * exception is ri_Check_Pk_Match(), which uses the PK table for both (and
2352  * sets queryno to RI_PLAN_CHECK_LOOKUPPK_FROM_PK). We might eventually
2353  * need some less klugy way to determine this.
2354  */
2356  {
2357  source_rel = fk_rel;
2358  source_is_pk = false;
2359  }
2360  else
2361  {
2362  source_rel = pk_rel;
2363  source_is_pk = true;
2364  }
2365 
2366  /* Extract the parameters to be passed into the query */
2367  if (newslot)
2368  {
2369  ri_ExtractValues(source_rel, newslot, riinfo, source_is_pk,
2370  vals, nulls);
2371  if (oldslot)
2372  ri_ExtractValues(source_rel, oldslot, riinfo, source_is_pk,
2373  vals + riinfo->nkeys, nulls + riinfo->nkeys);
2374  }
2375  else
2376  {
2377  ri_ExtractValues(source_rel, oldslot, riinfo, source_is_pk,
2378  vals, nulls);
2379  }
2380 
2381  /*
2382  * In READ COMMITTED mode, we just need to use an up-to-date regular
2383  * snapshot, and we will see all rows that could be interesting. But in
2384  * transaction-snapshot mode, we can't change the transaction snapshot. If
2385  * the caller passes detectNewRows == false then it's okay to do the query
2386  * with the transaction snapshot; otherwise we use a current snapshot, and
2387  * tell the executor to error out if it finds any rows under the current
2388  * snapshot that wouldn't be visible per the transaction snapshot. Note
2389  * that SPI_execute_snapshot will register the snapshots, so we don't need
2390  * to bother here.
2391  */
2392  if (IsolationUsesXactSnapshot() && detectNewRows)
2393  {
2394  CommandCounterIncrement(); /* be sure all my own work is visible */
2395  test_snapshot = GetLatestSnapshot();
2396  crosscheck_snapshot = GetTransactionSnapshot();
2397  }
2398  else
2399  {
2400  /* the default SPI behavior is okay */
2401  test_snapshot = InvalidSnapshot;
2402  crosscheck_snapshot = InvalidSnapshot;
2403  }
2404 
2405  /*
2406  * If this is a select query (e.g., for a 'no action' or 'restrict'
2407  * trigger), we only need to see if there is a single row in the table,
2408  * matching the key. Otherwise, limit = 0 - because we want the query to
2409  * affect ALL the matching rows.
2410  */
2411  limit = (expect_OK == SPI_OK_SELECT) ? 1 : 0;
2412 
2413  /* Switch to proper UID to perform check as */
2414  GetUserIdAndSecContext(&save_userid, &save_sec_context);
2415  SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
2416  save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
2418 
2419  /* Finally we can run the query. */
2420  spi_result = SPI_execute_snapshot(qplan,
2421  vals, nulls,
2422  test_snapshot, crosscheck_snapshot,
2423  false, false, limit);
2424 
2425  /* Restore UID and security context */
2426  SetUserIdAndSecContext(save_userid, save_sec_context);
2427 
2428  /* Check result */
2429  if (spi_result < 0)
2430  elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
2431 
2432  if (expect_OK >= 0 && spi_result != expect_OK)
2433  ereport(ERROR,
2434  (errcode(ERRCODE_INTERNAL_ERROR),
2435  errmsg("referential integrity query on \"%s\" from constraint \"%s\" on \"%s\" gave unexpected result",
2436  RelationGetRelationName(pk_rel),
2437  NameStr(riinfo->conname),
2438  RelationGetRelationName(fk_rel)),
2439  errhint("This is most likely due to a rule having rewritten the query.")));
2440 
2441  /* XXX wouldn't it be clearer to do this part at the caller? */
2443  expect_OK == SPI_OK_SELECT &&
2445  ri_ReportViolation(riinfo,
2446  pk_rel, fk_rel,
2447  newslot ? newslot : oldslot,
2448  NULL,
2449  qkey->constr_queryno, false);
2450 
2451  return SPI_processed != 0;
2452 }
2453 
2454 /*
2455  * Extract fields from a tuple into Datum/nulls arrays
2456  */
2457 static void
2459  const RI_ConstraintInfo *riinfo, bool rel_is_pk,
2460  Datum *vals, char *nulls)
2461 {
2462  const int16 *attnums;
2463  bool isnull;
2464 
2465  if (rel_is_pk)
2466  attnums = riinfo->pk_attnums;
2467  else
2468  attnums = riinfo->fk_attnums;
2469 
2470  for (int i = 0; i < riinfo->nkeys; i++)
2471  {
2472  vals[i] = slot_getattr(slot, attnums[i], &isnull);
2473  nulls[i] = isnull ? 'n' : ' ';
2474  }
2475 }
2476 
2477 /*
2478  * Produce an error report
2479  *
2480  * If the failed constraint was on insert/update to the FK table,
2481  * we want the key names and values extracted from there, and the error
2482  * message to look like 'key blah is not present in PK'.
2483  * Otherwise, the attr names and values come from the PK table and the
2484  * message looks like 'key blah is still referenced from FK'.
2485  */
2486 static void
2488  Relation pk_rel, Relation fk_rel,
2489  TupleTableSlot *violatorslot, TupleDesc tupdesc,
2490  int queryno, bool partgone)
2491 {
2492  StringInfoData key_names;
2493  StringInfoData key_values;
2494  bool onfk;
2495  const int16 *attnums;
2496  Oid rel_oid;
2497  AclResult aclresult;
2498  bool has_perm = true;
2499 
2500  /*
2501  * Determine which relation to complain about. If tupdesc wasn't passed
2502  * by caller, assume the violator tuple came from there.
2503  */
2504  onfk = (queryno == RI_PLAN_CHECK_LOOKUPPK);
2505  if (onfk)
2506  {
2507  attnums = riinfo->fk_attnums;
2508  rel_oid = fk_rel->rd_id;
2509  if (tupdesc == NULL)
2510  tupdesc = fk_rel->rd_att;
2511  }
2512  else
2513  {
2514  attnums = riinfo->pk_attnums;
2515  rel_oid = pk_rel->rd_id;
2516  if (tupdesc == NULL)
2517  tupdesc = pk_rel->rd_att;
2518  }
2519 
2520  /*
2521  * Check permissions- if the user does not have access to view the data in
2522  * any of the key columns then we don't include the errdetail() below.
2523  *
2524  * Check if RLS is enabled on the relation first. If so, we don't return
2525  * any specifics to avoid leaking data.
2526  *
2527  * Check table-level permissions next and, failing that, column-level
2528  * privileges.
2529  *
2530  * When a partition at the referenced side is being detached/dropped, we
2531  * needn't check, since the user must be the table owner anyway.
2532  */
2533  if (partgone)
2534  has_perm = true;
2535  else if (check_enable_rls(rel_oid, InvalidOid, true) != RLS_ENABLED)
2536  {
2537  aclresult = pg_class_aclcheck(rel_oid, GetUserId(), ACL_SELECT);
2538  if (aclresult != ACLCHECK_OK)
2539  {
2540  /* Try for column-level permissions */
2541  for (int idx = 0; idx < riinfo->nkeys; idx++)
2542  {
2543  aclresult = pg_attribute_aclcheck(rel_oid, attnums[idx],
2544  GetUserId(),
2545  ACL_SELECT);
2546 
2547  /* No access to the key */
2548  if (aclresult != ACLCHECK_OK)
2549  {
2550  has_perm = false;
2551  break;
2552  }
2553  }
2554  }
2555  }
2556  else
2557  has_perm = false;
2558 
2559  if (has_perm)
2560  {
2561  /* Get printable versions of the keys involved */
2562  initStringInfo(&key_names);
2563  initStringInfo(&key_values);
2564  for (int idx = 0; idx < riinfo->nkeys; idx++)
2565  {
2566  int fnum = attnums[idx];
2567  Form_pg_attribute att = TupleDescAttr(tupdesc, fnum - 1);
2568  char *name,
2569  *val;
2570  Datum datum;
2571  bool isnull;
2572 
2573  name = NameStr(att->attname);
2574 
2575  datum = slot_getattr(violatorslot, fnum, &isnull);
2576  if (!isnull)
2577  {
2578  Oid foutoid;
2579  bool typisvarlena;
2580 
2581  getTypeOutputInfo(att->atttypid, &foutoid, &typisvarlena);
2582  val = OidOutputFunctionCall(foutoid, datum);
2583  }
2584  else
2585  val = "null";
2586 
2587  if (idx > 0)
2588  {
2589  appendStringInfoString(&key_names, ", ");
2590  appendStringInfoString(&key_values, ", ");
2591  }
2592  appendStringInfoString(&key_names, name);
2593  appendStringInfoString(&key_values, val);
2594  }
2595  }
2596 
2597  if (partgone)
2598  ereport(ERROR,
2599  (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
2600  errmsg("removing partition \"%s\" violates foreign key constraint \"%s\"",
2601  RelationGetRelationName(pk_rel),
2602  NameStr(riinfo->conname)),
2603  errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
2604  key_names.data, key_values.data,
2605  RelationGetRelationName(fk_rel)),
2606  errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2607  else if (onfk)
2608  ereport(ERROR,
2609  (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
2610  errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
2611  RelationGetRelationName(fk_rel),
2612  NameStr(riinfo->conname)),
2613  has_perm ?
2614  errdetail("Key (%s)=(%s) is not present in table \"%s\".",
2615  key_names.data, key_values.data,
2616  RelationGetRelationName(pk_rel)) :
2617  errdetail("Key is not present in table \"%s\".",
2618  RelationGetRelationName(pk_rel)),
2619  errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2620  else
2621  ereport(ERROR,
2622  (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
2623  errmsg("update or delete on table \"%s\" violates foreign key constraint \"%s\" on table \"%s\"",
2624  RelationGetRelationName(pk_rel),
2625  NameStr(riinfo->conname),
2626  RelationGetRelationName(fk_rel)),
2627  has_perm ?
2628  errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
2629  key_names.data, key_values.data,
2630  RelationGetRelationName(fk_rel)) :
2631  errdetail("Key is still referenced from table \"%s\".",
2632  RelationGetRelationName(fk_rel)),
2633  errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2634 }
2635 
2636 
2637 /*
2638  * ri_NullCheck -
2639  *
2640  * Determine the NULL state of all key values in a tuple
2641  *
2642  * Returns one of RI_KEYS_ALL_NULL, RI_KEYS_NONE_NULL or RI_KEYS_SOME_NULL.
2643  */
2644 static int
2646  TupleTableSlot *slot,
2647  const RI_ConstraintInfo *riinfo, bool rel_is_pk)
2648 {
2649  const int16 *attnums;
2650  bool allnull = true;
2651  bool nonenull = true;
2652 
2653  if (rel_is_pk)
2654  attnums = riinfo->pk_attnums;
2655  else
2656  attnums = riinfo->fk_attnums;
2657 
2658  for (int i = 0; i < riinfo->nkeys; i++)
2659  {
2660  if (slot_attisnull(slot, attnums[i]))
2661  nonenull = false;
2662  else
2663  allnull = false;
2664  }
2665 
2666  if (allnull)
2667  return RI_KEYS_ALL_NULL;
2668 
2669  if (nonenull)
2670  return RI_KEYS_NONE_NULL;
2671 
2672  return RI_KEYS_SOME_NULL;
2673 }
2674 
2675 
2676 /*
2677  * ri_InitHashTables -
2678  *
2679  * Initialize our internal hash tables.
2680  */
2681 static void
2683 {
2684  HASHCTL ctl;
2685 
2686  ctl.keysize = sizeof(Oid);
2687  ctl.entrysize = sizeof(RI_ConstraintInfo);
2688  ri_constraint_cache = hash_create("RI constraint cache",
2690  &ctl, HASH_ELEM | HASH_BLOBS);
2691 
2692  /* Arrange to flush cache on pg_constraint changes */
2695  (Datum) 0);
2696 
2697  ctl.keysize = sizeof(RI_QueryKey);
2698  ctl.entrysize = sizeof(RI_QueryHashEntry);
2699  ri_query_cache = hash_create("RI query cache",
2701  &ctl, HASH_ELEM | HASH_BLOBS);
2702 
2703  ctl.keysize = sizeof(RI_CompareKey);
2704  ctl.entrysize = sizeof(RI_CompareHashEntry);
2705  ri_compare_cache = hash_create("RI compare cache",
2707  &ctl, HASH_ELEM | HASH_BLOBS);
2708 }
2709 
2710 
2711 /*
2712  * ri_FetchPreparedPlan -
2713  *
2714  * Lookup for a query key in our private hash table of prepared
2715  * and saved SPI execution plans. Return the plan if found or NULL.
2716  */
2717 static SPIPlanPtr
2719 {
2720  RI_QueryHashEntry *entry;
2721  SPIPlanPtr plan;
2722 
2723  /*
2724  * On the first call initialize the hashtable
2725  */
2726  if (!ri_query_cache)
2728 
2729  /*
2730  * Lookup for the key
2731  */
2733  key,
2734  HASH_FIND, NULL);
2735  if (entry == NULL)
2736  return NULL;
2737 
2738  /*
2739  * Check whether the plan is still valid. If it isn't, we don't want to
2740  * simply rely on plancache.c to regenerate it; rather we should start
2741  * from scratch and rebuild the query text too. This is to cover cases
2742  * such as table/column renames. We depend on the plancache machinery to
2743  * detect possible invalidations, though.
2744  *
2745  * CAUTION: this check is only trustworthy if the caller has already
2746  * locked both FK and PK rels.
2747  */
2748  plan = entry->plan;
2749  if (plan && SPI_plan_is_valid(plan))
2750  return plan;
2751 
2752  /*
2753  * Otherwise we might as well flush the cached plan now, to free a little
2754  * memory space before we make a new one.
2755  */
2756  entry->plan = NULL;
2757  if (plan)
2758  SPI_freeplan(plan);
2759 
2760  return NULL;
2761 }
2762 
2763 
2764 /*
2765  * ri_HashPreparedPlan -
2766  *
2767  * Add another plan to our private SPI query plan hashtable.
2768  */
2769 static void
2771 {
2772  RI_QueryHashEntry *entry;
2773  bool found;
2774 
2775  /*
2776  * On the first call initialize the hashtable
2777  */
2778  if (!ri_query_cache)
2780 
2781  /*
2782  * Add the new plan. We might be overwriting an entry previously found
2783  * invalid by ri_FetchPreparedPlan.
2784  */
2786  key,
2787  HASH_ENTER, &found);
2788  Assert(!found || entry->plan == NULL);
2789  entry->plan = plan;
2790 }
2791 
2792 
2793 /*
2794  * ri_KeysEqual -
2795  *
2796  * Check if all key values in OLD and NEW are equal.
2797  *
2798  * Note: at some point we might wish to redefine this as checking for
2799  * "IS NOT DISTINCT" rather than "=", that is, allow two nulls to be
2800  * considered equal. Currently there is no need since all callers have
2801  * previously found at least one of the rows to contain no nulls.
2802  */
2803 static bool
2805  const RI_ConstraintInfo *riinfo, bool rel_is_pk)
2806 {
2807  const int16 *attnums;
2808 
2809  if (rel_is_pk)
2810  attnums = riinfo->pk_attnums;
2811  else
2812  attnums = riinfo->fk_attnums;
2813 
2814  /* XXX: could be worthwhile to fetch all necessary attrs at once */
2815  for (int i = 0; i < riinfo->nkeys; i++)
2816  {
2817  Datum oldvalue;
2818  Datum newvalue;
2819  bool isnull;
2820 
2821  /*
2822  * Get one attribute's oldvalue. If it is NULL - they're not equal.
2823  */
2824  oldvalue = slot_getattr(oldslot, attnums[i], &isnull);
2825  if (isnull)
2826  return false;
2827 
2828  /*
2829  * Get one attribute's newvalue. If it is NULL - they're not equal.
2830  */
2831  newvalue = slot_getattr(newslot, attnums[i], &isnull);
2832  if (isnull)
2833  return false;
2834 
2835  if (rel_is_pk)
2836  {
2837  /*
2838  * If we are looking at the PK table, then do a bytewise
2839  * comparison. We must propagate PK changes if the value is
2840  * changed to one that "looks" different but would compare as
2841  * equal using the equality operator. This only makes a
2842  * difference for ON UPDATE CASCADE, but for consistency we treat
2843  * all changes to the PK the same.
2844  */
2845  Form_pg_attribute att = TupleDescAttr(oldslot->tts_tupleDescriptor, attnums[i] - 1);
2846 
2847  if (!datum_image_eq(oldvalue, newvalue, att->attbyval, att->attlen))
2848  return false;
2849  }
2850  else
2851  {
2852  /*
2853  * For the FK table, compare with the appropriate equality
2854  * operator. Changes that compare equal will still satisfy the
2855  * constraint after the update.
2856  */
2857  if (!ri_AttributesEqual(riinfo->ff_eq_oprs[i], RIAttType(rel, attnums[i]),
2858  oldvalue, newvalue))
2859  return false;
2860  }
2861  }
2862 
2863  return true;
2864 }
2865 
2866 
2867 /*
2868  * ri_AttributesEqual -
2869  *
2870  * Call the appropriate equality comparison operator for two values.
2871  *
2872  * NB: we have already checked that neither value is null.
2873  */
2874 static bool
2875 ri_AttributesEqual(Oid eq_opr, Oid typeid,
2876  Datum oldvalue, Datum newvalue)
2877 {
2878  RI_CompareHashEntry *entry = ri_HashCompareOp(eq_opr, typeid);
2879 
2880  /* Do we need to cast the values? */
2881  if (OidIsValid(entry->cast_func_finfo.fn_oid))
2882  {
2883  oldvalue = FunctionCall3(&entry->cast_func_finfo,
2884  oldvalue,
2885  Int32GetDatum(-1), /* typmod */
2886  BoolGetDatum(false)); /* implicit coercion */
2887  newvalue = FunctionCall3(&entry->cast_func_finfo,
2888  newvalue,
2889  Int32GetDatum(-1), /* typmod */
2890  BoolGetDatum(false)); /* implicit coercion */
2891  }
2892 
2893  /*
2894  * Apply the comparison operator.
2895  *
2896  * Note: This function is part of a call stack that determines whether an
2897  * update to a row is significant enough that it needs checking or action
2898  * on the other side of a foreign-key constraint. Therefore, the
2899  * comparison here would need to be done with the collation of the *other*
2900  * table. For simplicity (e.g., we might not even have the other table
2901  * open), we'll just use the default collation here, which could lead to
2902  * some false negatives. All this would break if we ever allow
2903  * database-wide collations to be nondeterministic.
2904  */
2906  DEFAULT_COLLATION_OID,
2907  oldvalue, newvalue));
2908 }
2909 
2910 /*
2911  * ri_HashCompareOp -
2912  *
2913  * See if we know how to compare two values, and create a new hash entry
2914  * if not.
2915  */
2916 static RI_CompareHashEntry *
2917 ri_HashCompareOp(Oid eq_opr, Oid typeid)
2918 {
2920  RI_CompareHashEntry *entry;
2921  bool found;
2922 
2923  /*
2924  * On the first call initialize the hashtable
2925  */
2926  if (!ri_compare_cache)
2928 
2929  /*
2930  * Find or create a hash entry. Note we're assuming RI_CompareKey
2931  * contains no struct padding.
2932  */
2933  key.eq_opr = eq_opr;
2934  key.typeid = typeid;
2936  &key,
2937  HASH_ENTER, &found);
2938  if (!found)
2939  entry->valid = false;
2940 
2941  /*
2942  * If not already initialized, do so. Since we'll keep this hash entry
2943  * for the life of the backend, put any subsidiary info for the function
2944  * cache structs into TopMemoryContext.
2945  */
2946  if (!entry->valid)
2947  {
2948  Oid lefttype,
2949  righttype,
2950  castfunc;
2951  CoercionPathType pathtype;
2952 
2953  /* We always need to know how to call the equality operator */
2954  fmgr_info_cxt(get_opcode(eq_opr), &entry->eq_opr_finfo,
2956 
2957  /*
2958  * If we chose to use a cast from FK to PK type, we may have to apply
2959  * the cast function to get to the operator's input type.
2960  *
2961  * XXX eventually it would be good to support array-coercion cases
2962  * here and in ri_AttributesEqual(). At the moment there is no point
2963  * because cases involving nonidentical array types will be rejected
2964  * at constraint creation time.
2965  *
2966  * XXX perhaps also consider supporting CoerceViaIO? No need at the
2967  * moment since that will never be generated for implicit coercions.
2968  */
2969  op_input_types(eq_opr, &lefttype, &righttype);
2970  Assert(lefttype == righttype);
2971  if (typeid == lefttype)
2972  castfunc = InvalidOid; /* simplest case */
2973  else
2974  {
2975  pathtype = find_coercion_pathway(lefttype, typeid,
2977  &castfunc);
2978  if (pathtype != COERCION_PATH_FUNC &&
2979  pathtype != COERCION_PATH_RELABELTYPE)
2980  {
2981  /*
2982  * The declared input type of the eq_opr might be a
2983  * polymorphic type such as ANYARRAY or ANYENUM, or other
2984  * special cases such as RECORD; find_coercion_pathway
2985  * currently doesn't subsume these special cases.
2986  */
2987  if (!IsBinaryCoercible(typeid, lefttype))
2988  elog(ERROR, "no conversion function from %s to %s",
2989  format_type_be(typeid),
2990  format_type_be(lefttype));
2991  }
2992  }
2993  if (OidIsValid(castfunc))
2994  fmgr_info_cxt(castfunc, &entry->cast_func_finfo,
2996  else
2998  entry->valid = true;
2999  }
3000 
3001  return entry;
3002 }
3003 
3004 
3005 /*
3006  * Given a trigger function OID, determine whether it is an RI trigger,
3007  * and if so whether it is attached to PK or FK relation.
3008  */
3009 int
3011 {
3012  switch (tgfoid)
3013  {
3014  case F_RI_FKEY_CASCADE_DEL:
3015  case F_RI_FKEY_CASCADE_UPD:
3016  case F_RI_FKEY_RESTRICT_DEL:
3017  case F_RI_FKEY_RESTRICT_UPD:
3018  case F_RI_FKEY_SETNULL_DEL:
3019  case F_RI_FKEY_SETNULL_UPD:
3020  case F_RI_FKEY_SETDEFAULT_DEL:
3021  case F_RI_FKEY_SETDEFAULT_UPD:
3022  case F_RI_FKEY_NOACTION_DEL:
3023  case F_RI_FKEY_NOACTION_UPD:
3024  return RI_TRIGGER_PK;
3025 
3026  case F_RI_FKEY_CHECK_INS:
3027  case F_RI_FKEY_CHECK_UPD:
3028  return RI_TRIGGER_FK;
3029  }
3030 
3031  return RI_TRIGGER_NONE;
3032 }
Datum idx(PG_FUNCTION_ARGS)
Definition: _int_op.c:259
AclResult
Definition: acl.h:181
@ ACLCHECK_OK
Definition: acl.h:182
bool has_bypassrls_privilege(Oid roleid)
Definition: aclchk.c:4057
AclResult pg_attribute_aclcheck(Oid table_oid, AttrNumber attnum, Oid roleid, AclMode mode)
Definition: aclchk.c:3779
bool object_ownercheck(Oid classid, Oid objectid, Oid roleid)
Definition: aclchk.c:3961
AclResult pg_class_aclcheck(Oid table_oid, Oid roleid, AclMode mode)
Definition: aclchk.c:3908
Bitmapset * bms_add_member(Bitmapset *a, int x)
Definition: bitmapset.c:753
#define NameStr(name)
Definition: c.h:735
unsigned int uint32
Definition: c.h:495
signed short int16
Definition: c.h:482
signed int int32
Definition: c.h:483
#define pg_attribute_noreturn()
Definition: c.h:206
uint32 TransactionId
Definition: c.h:641
#define OidIsValid(objectId)
Definition: c.h:764
bool datum_image_eq(Datum value1, Datum value2, bool typByVal, int typLen)
Definition: datum.c:266
void * hash_search(HTAB *hashp, const void *keyPtr, HASHACTION action, bool *foundPtr)
Definition: dynahash.c:953
HTAB * hash_create(const char *tabname, long nelem, const HASHCTL *info, int flags)
Definition: dynahash.c:350
int errdetail(const char *fmt,...)
Definition: elog.c:1202
int errhint(const char *fmt,...)
Definition: elog.c:1316
int errcode(int sqlerrcode)
Definition: elog.c:858
int errmsg(const char *fmt,...)
Definition: elog.c:1069
#define ERROR
Definition: elog.h:39
#define ereport(elevel,...)
Definition: elog.h:149
bool ExecCheckPermissions(List *rangeTable, List *rteperminfos, bool ereport_on_violation)
Definition: execMain.c:581
const TupleTableSlotOps TTSOpsVirtual
Definition: execTuples.c:83
TupleTableSlot * ExecStoreVirtualTuple(TupleTableSlot *slot)
Definition: execTuples.c:1553
void ExecDropSingleTupleTableSlot(TupleTableSlot *slot)
Definition: execTuples.c:1255
TupleTableSlot * MakeSingleTupleTableSlot(TupleDesc tupdesc, const TupleTableSlotOps *tts_ops)
Definition: execTuples.c:1239
Datum FunctionCall2Coll(FmgrInfo *flinfo, Oid collation, Datum arg1, Datum arg2)
Definition: fmgr.c:1132
void fmgr_info_cxt(Oid functionId, FmgrInfo *finfo, MemoryContext mcxt)
Definition: fmgr.c:137
char * OidOutputFunctionCall(Oid functionId, Datum val)
Definition: fmgr.c:1746
#define FunctionCall3(flinfo, arg1, arg2, arg3)
Definition: fmgr.h:664
#define PG_FUNCTION_ARGS
Definition: fmgr.h:193
char * format_type_be(Oid type_oid)
Definition: format_type.c:343
int maintenance_work_mem
Definition: globals.c:127
int NewGUCNestLevel(void)
Definition: guc.c:2201
void AtEOXact_GUC(bool isCommit, int nestLevel)
Definition: guc.c:2215
int set_config_option(const char *name, const char *value, GucContext context, GucSource source, GucAction action, bool changeVal, int elevel, bool is_reload)
Definition: guc.c:3284
@ GUC_ACTION_SAVE
Definition: guc.h:199
@ PGC_S_SESSION
Definition: guc.h:122
@ PGC_USERSET
Definition: guc.h:75
void heap_deform_tuple(HeapTuple tuple, TupleDesc tupleDesc, Datum *values, bool *isnull)
Definition: heaptuple.c:1337
@ HASH_FIND
Definition: hsearch.h:113
@ HASH_ENTER
Definition: hsearch.h:114
#define HASH_ELEM
Definition: hsearch.h:95
#define HASH_BLOBS
Definition: hsearch.h:97
#define HeapTupleIsValid(tuple)
Definition: htup.h:78
#define GETSTRUCT(TUP)
Definition: htup_details.h:653
#define dclist_container(type, membername, ptr)
Definition: ilist.h:947
static void dclist_push_tail(dclist_head *head, dlist_node *node)
Definition: ilist.h:709
static uint32 dclist_count(const dclist_head *head)
Definition: ilist.h:932
static void dclist_delete_from(dclist_head *head, dlist_node *node)
Definition: ilist.h:763
#define dclist_foreach_modify(iter, lhead)
Definition: ilist.h:973
#define funcname
Definition: indent_codes.h:69
long val
Definition: informix.c:664
void CacheRegisterSyscacheCallback(int cacheid, SyscacheCallbackFunction func, Datum arg)
Definition: inval.c:1519
int j
Definition: isn.c:74
int i
Definition: isn.c:73
if(TABLE==NULL||TABLE_index==NULL)
Definition: isn.c:77
Assert(fmt[strlen(fmt) - 1] !='\n')
List * lappend(List *list, void *datum)
Definition: list.c:338
#define AccessShareLock
Definition: lockdefs.h:36
#define RowShareLock
Definition: lockdefs.h:37
#define RowExclusiveLock
Definition: lockdefs.h:38
char * get_namespace_name(Oid nspid)
Definition: lsyscache.c:3348
void getTypeOutputInfo(Oid type, Oid *typOutput, bool *typIsVarlena)
Definition: lsyscache.c:2889
RegProcedure get_opcode(Oid opno)
Definition: lsyscache.c:1289
bool get_collation_isdeterministic(Oid colloid)
Definition: lsyscache.c:1080
void op_input_types(Oid opno, Oid *lefttype, Oid *righttype)
Definition: lsyscache.c:1362
MemoryContext TopMemoryContext
Definition: mcxt.c:141
#define SECURITY_NOFORCE_RLS
Definition: miscadmin.h:315
#define SECURITY_LOCAL_USERID_CHANGE
Definition: miscadmin.h:313
void GetUserIdAndSecContext(Oid *userid, int *sec_context)
Definition: miscinit.c:630
Oid GetUserId(void)
Definition: miscinit.c:509
void SetUserIdAndSecContext(Oid userid, int sec_context)
Definition: miscinit.c:637
#define makeNode(_type_)
Definition: nodes.h:176
CoercionPathType find_coercion_pathway(Oid targetTypeId, Oid sourceTypeId, CoercionContext ccontext, Oid *funcid)
bool IsBinaryCoercible(Oid srctype, Oid targettype)
CoercionPathType
Definition: parse_coerce.h:25
@ COERCION_PATH_FUNC
Definition: parse_coerce.h:27
@ COERCION_PATH_RELABELTYPE
Definition: parse_coerce.h:28
#define FKCONSTR_MATCH_SIMPLE
Definition: parsenodes.h:2588
@ RTE_RELATION
Definition: parsenodes.h:1013
#define FKCONSTR_MATCH_PARTIAL
Definition: parsenodes.h:2587
#define ACL_SELECT
Definition: parsenodes.h:84
#define FKCONSTR_MATCH_FULL
Definition: parsenodes.h:2586
NameData attname
Definition: pg_attribute.h:41
FormData_pg_attribute * Form_pg_attribute
Definition: pg_attribute.h:209
void * arg
FormData_pg_collation * Form_pg_collation
Definition: pg_collation.h:58
void DeconstructFkConstraintRow(HeapTuple tuple, int *numfks, AttrNumber *conkey, AttrNumber *confkey, Oid *pf_eq_oprs, Oid *pp_eq_oprs, Oid *ff_eq_oprs, int *num_fk_del_set_cols, AttrNumber *fk_del_set_cols)
FormData_pg_constraint * Form_pg_constraint
static int list_length(const List *l)
Definition: pg_list.h:152
#define NIL
Definition: pg_list.h:68
#define plan(x)
Definition: pg_regress.c:154
static char * buf
Definition: pg_test_fsync.c:67
#define sprintf
Definition: port.h:240
#define snprintf
Definition: port.h:238
static bool DatumGetBool(Datum X)
Definition: postgres.h:90
static Datum PointerGetDatum(const void *X)
Definition: postgres.h:322
uintptr_t Datum
Definition: postgres.h:64
static Datum BoolGetDatum(bool X)
Definition: postgres.h:102
static Datum ObjectIdGetDatum(Oid X)
Definition: postgres.h:252
static TransactionId DatumGetTransactionId(Datum X)
Definition: postgres.h:262
static Datum Int32GetDatum(int32 X)
Definition: postgres.h:212
#define InvalidOid
Definition: postgres_ext.h:36
unsigned int Oid
Definition: postgres_ext.h:31
@ COERCION_IMPLICIT
Definition: primnodes.h:641
#define RelationGetForm(relation)
Definition: rel.h:498
#define RelationGetRelid(relation)
Definition: rel.h:504
#define RelationGetDescr(relation)
Definition: rel.h:530
#define RelationGetRelationName(relation)
Definition: rel.h:538
#define RelationGetNamespace(relation)
Definition: rel.h:545
int errtableconstraint(Relation rel, const char *conname)
Definition: relcache.c:5989
static Datum ri_set(TriggerData *trigdata, bool is_set_null, int tgkind)
Definition: ri_triggers.c:1034
#define RI_TRIGTYPE_INSERT
Definition: ri_triggers.c:92
struct RI_ConstraintInfo RI_ConstraintInfo
static const RI_ConstraintInfo * ri_LoadConstraintInfo(Oid constraintOid)
Definition: ri_triggers.c:2121
static Datum RI_FKey_check(TriggerData *trigdata)
Definition: ri_triggers.c:242
#define RI_PLAN_SETNULL_ONUPDATE
Definition: ri_triggers.c:81
#define RI_PLAN_CASCADE_ONUPDATE
Definition: ri_triggers.c:77
#define RI_TRIGTYPE_DELETE
Definition: ri_triggers.c:94
Datum RI_FKey_setnull_del(PG_FUNCTION_ARGS)
Definition: ri_triggers.c:973
static bool ri_PerformCheck(const RI_ConstraintInfo *riinfo, RI_QueryKey *qkey, SPIPlanPtr qplan, Relation fk_rel, Relation pk_rel, TupleTableSlot *oldslot, TupleTableSlot *newslot, bool detectNewRows, int expect_OK)
Definition: ri_triggers.c:2321
static void ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan)
Definition: ri_triggers.c:2770
static void quoteOneName(char *buffer, const char *name)
Definition: ri_triggers.c:1882
bool RI_FKey_pk_upd_check_required(Trigger *trigger, Relation pk_rel, TupleTableSlot *oldslot, TupleTableSlot *newslot)
Definition: ri_triggers.c:1229
#define RI_PLAN_LAST_ON_PK
Definition: ri_triggers.c:74
#define RIAttType(rel, attnum)
Definition: ri_triggers.c:89
static void ri_GenerateQualCollation(StringInfo buf, Oid collation)
Definition: ri_triggers.c:1948
Datum RI_FKey_cascade_del(PG_FUNCTION_ARGS)
Definition: ri_triggers.c:746
#define RI_KEYS_SOME_NULL
Definition: ri_triggers.c:67
Datum RI_FKey_check_upd(PG_FUNCTION_ARGS)
Definition: ri_triggers.c:443
static HTAB * ri_query_cache
Definition: ri_triggers.c:177
#define MAX_QUOTED_REL_NAME_LEN
Definition: ri_triggers.c:86
static void ri_ReportViolation(const RI_ConstraintInfo *riinfo, Relation pk_rel, Relation fk_rel, TupleTableSlot *violatorslot, TupleDesc tupdesc, int queryno, bool partgone) pg_attribute_noreturn()
Definition: ri_triggers.c:2487
Datum RI_FKey_restrict_upd(PG_FUNCTION_ARGS)
Definition: ri_triggers.c:611
static void InvalidateConstraintCacheCallBack(Datum arg, int cacheid, uint32 hashvalue)
Definition: ri_triggers.c:2237
static Datum ri_restrict(TriggerData *trigdata, bool is_no_action)
Definition: ri_triggers.c:627
Datum RI_FKey_restrict_del(PG_FUNCTION_ARGS)
Definition: ri_triggers.c:574
#define RI_PLAN_RESTRICT
Definition: ri_triggers.c:79
static bool ri_AttributesEqual(Oid eq_opr, Oid typeid, Datum oldvalue, Datum newvalue)
Definition: ri_triggers.c:2875
Datum RI_FKey_noaction_del(PG_FUNCTION_ARGS)
Definition: ri_triggers.c:554
static void quoteRelationName(char *buffer, Relation rel)
Definition: ri_triggers.c:1902
static int ri_NullCheck(TupleDesc tupDesc, TupleTableSlot *slot, const RI_ConstraintInfo *riinfo, bool rel_is_pk)
Definition: ri_triggers.c:2645
static void ri_GenerateQual(StringInfo buf, const char *sep, const char *leftop, Oid leftoptype, Oid opoid, const char *rightop, Oid rightoptype)
Definition: ri_triggers.c:1919
struct RI_QueryKey RI_QueryKey
static bool ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot, const RI_ConstraintInfo *riinfo, bool rel_is_pk)
Definition: ri_triggers.c:2804
struct RI_CompareHashEntry RI_CompareHashEntry
static RI_CompareHashEntry * ri_HashCompareOp(Oid eq_opr, Oid typeid)
Definition: ri_triggers.c:2917
#define RI_PLAN_CHECK_LOOKUPPK_FROM_PK
Definition: ri_triggers.c:73
#define RIAttCollation(rel, attnum)
Definition: ri_triggers.c:90
static dclist_head ri_constraint_cache_valid_list
Definition: ri_triggers.c:179
static Oid get_ri_constraint_root(Oid constrOid)
Definition: ri_triggers.c:2203
Datum RI_FKey_check_ins(PG_FUNCTION_ARGS)
Definition: ri_triggers.c:427
struct RI_QueryHashEntry RI_QueryHashEntry
#define RI_KEYS_ALL_NULL
Definition: ri_triggers.c:66
static HTAB * ri_compare_cache
Definition: ri_triggers.c:178
#define RI_KEYS_NONE_NULL
Definition: ri_triggers.c:68
#define RI_INIT_QUERYHASHSIZE
Definition: ri_triggers.c:64
static const RI_ConstraintInfo * ri_FetchConstraintInfo(Trigger *trigger, Relation trig_rel, bool rel_is_pk)
Definition: ri_triggers.c:2067
static void ri_BuildQueryKey(RI_QueryKey *key, const RI_ConstraintInfo *riinfo, int32 constr_queryno)
Definition: ri_triggers.c:1989
#define RI_PLAN_CASCADE_ONDELETE
Definition: ri_triggers.c:76
Datum RI_FKey_setnull_upd(PG_FUNCTION_ARGS)
Definition: ri_triggers.c:988
#define RI_PLAN_SETDEFAULT_ONDELETE
Definition: ri_triggers.c:82
Datum RI_FKey_setdefault_del(PG_FUNCTION_ARGS)
Definition: ri_triggers.c:1003
#define RI_PLAN_SETDEFAULT_ONUPDATE
Definition: ri_triggers.c:83
#define RI_PLAN_CHECK_LOOKUPPK
Definition: ri_triggers.c:72
#define RI_PLAN_SETNULL_ONDELETE
Definition: ri_triggers.c:80
#define RI_INIT_CONSTRAINTHASHSIZE
Definition: ri_triggers.c:63
bool RI_Initial_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
Definition: ri_triggers.c:1368
static bool ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel, TupleTableSlot *oldslot, const RI_ConstraintInfo *riinfo)
Definition: ri_triggers.c:464
void RI_PartitionRemove_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
Definition: ri_triggers.c:1663
static SPIPlanPtr ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes, RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel)
Definition: ri_triggers.c:2278
#define MAX_QUOTED_NAME_LEN
Definition: ri_triggers.c:85
static void ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname, int tgkind)
Definition: ri_triggers.c:2021
#define RI_TRIGTYPE_UPDATE
Definition: ri_triggers.c:93
bool RI_FKey_fk_upd_check_required(Trigger *trigger, Relation fk_rel, TupleTableSlot *oldslot, TupleTableSlot *newslot)
Definition: ri_triggers.c:1261
int RI_FKey_trigger_type(Oid tgfoid)
Definition: ri_triggers.c:3010
Datum RI_FKey_cascade_upd(PG_FUNCTION_ARGS)
Definition: ri_triggers.c:852
Datum RI_FKey_noaction_upd(PG_FUNCTION_ARGS)
Definition: ri_triggers.c:591
static void ri_InitHashTables(void)
Definition: ri_triggers.c:2682
static void ri_ExtractValues(Relation rel, TupleTableSlot *slot, const RI_ConstraintInfo *riinfo, bool rel_is_pk, Datum *vals, char *nulls)
Definition: ri_triggers.c:2458
#define RIAttName(rel, attnum)
Definition: ri_triggers.c:88
#define RI_MAX_NUMKEYS
Definition: ri_triggers.c:61
static HTAB * ri_constraint_cache
Definition: ri_triggers.c:176
static SPIPlanPtr ri_FetchPreparedPlan(RI_QueryKey *key)
Definition: ri_triggers.c:2718
struct RI_CompareKey RI_CompareKey
Datum RI_FKey_setdefault_upd(PG_FUNCTION_ARGS)
Definition: ri_triggers.c:1018
int check_enable_rls(Oid relid, Oid checkAsUser, bool noError)
Definition: rls.c:52
@ RLS_ENABLED
Definition: rls.h:45
char * pg_get_partconstrdef_string(Oid partitionId, char *aliasname)
Definition: ruleutils.c:2099
void generate_operator_clause(StringInfo buf, const char *leftop, Oid leftoptype, Oid opoid, const char *rightop, Oid rightoptype)
Definition: ruleutils.c:12373
Snapshot GetTransactionSnapshot(void)
Definition: snapmgr.c:197
Snapshot GetLatestSnapshot(void)
Definition: snapmgr.c:272
#define SnapshotSelf
Definition: snapmgr.h:32
#define InvalidSnapshot
Definition: snapshot.h:123
bool SPI_plan_is_valid(SPIPlanPtr plan)
Definition: spi.c:1946
uint64 SPI_processed
Definition: spi.c:45
int SPI_freeplan(SPIPlanPtr plan)
Definition: spi.c:1023
SPITupleTable * SPI_tuptable
Definition: spi.c:46
int SPI_connect(void)
Definition: spi.c:95
int SPI_execute_snapshot(SPIPlanPtr plan, Datum *Values, const char *Nulls, Snapshot snapshot, Snapshot crosscheck_snapshot, bool read_only, bool fire_triggers, long tcount)
Definition: spi.c:771
int SPI_result
Definition: spi.c:47
const char * SPI_result_code_string(int code)
Definition: spi.c:1970
int SPI_finish(void)
Definition: spi.c:183
SPIPlanPtr SPI_prepare(const char *src, int nargs, Oid *argtypes)
Definition: spi.c:858
int SPI_keepplan(SPIPlanPtr plan)
Definition: spi.c:974
#define SPI_OK_UPDATE
Definition: spi.h:90
#define SPI_OK_DELETE
Definition: spi.h:89
#define SPI_OK_CONNECT
Definition: spi.h:82
#define SPI_OK_FINISH
Definition: spi.h:83
#define SPI_OK_SELECT
Definition: spi.h:86
void appendStringInfo(StringInfo str, const char *fmt,...)
Definition: stringinfo.c:91
void appendBinaryStringInfo(StringInfo str, const void *data, int datalen)
Definition: stringinfo.c:227
void appendStringInfoString(StringInfo str, const char *s)
Definition: stringinfo.c:176
void appendStringInfoChar(StringInfo str, char ch)
Definition: stringinfo.c:188
void initStringInfo(StringInfo str)
Definition: stringinfo.c:59
Definition: fmgr.h:57
Oid fn_oid
Definition: fmgr.h:59
fmNodePtr context
Definition: fmgr.h:88
Size keysize
Definition: hsearch.h:75
Size entrysize
Definition: hsearch.h:76
Definition: dynahash.c:220
Definition: pg_list.h:54
RI_CompareKey key
Definition: ri_triggers.c:166
FmgrInfo cast_func_finfo
Definition: ri_triggers.c:169
dlist_node valid_link
Definition: ri_triggers.c:127
int16 pk_attnums[RI_MAX_NUMKEYS]
Definition: ri_triggers.c:122
int16 fk_attnums[RI_MAX_NUMKEYS]
Definition: ri_triggers.c:123
Oid pp_eq_oprs[RI_MAX_NUMKEYS]
Definition: ri_triggers.c:125
Oid pf_eq_oprs[RI_MAX_NUMKEYS]
Definition: ri_triggers.c:124
int16 confdelsetcols[RI_MAX_NUMKEYS]
Definition: ri_triggers.c:118
Oid ff_eq_oprs[RI_MAX_NUMKEYS]
Definition: ri_triggers.c:126
SPIPlanPtr plan
Definition: ri_triggers.c:147
RI_QueryKey key
Definition: ri_triggers.c:146
int32 constr_queryno
Definition: ri_triggers.c:138
Bitmapset * selectedCols
Definition: parsenodes.h:1247
AclMode requiredPerms
Definition: parsenodes.h:1245
Index perminfoindex
Definition: parsenodes.h:1075
RTEKind rtekind
Definition: parsenodes.h:1032
TupleDesc rd_att
Definition: rel.h:112
Oid rd_id
Definition: rel.h:113
Form_pg_class rd_rel
Definition: rel.h:111
TupleDesc tupdesc
Definition: spi.h:25
HeapTuple * vals
Definition: spi.h:26
Relation tg_relation
Definition: trigger.h:35
TriggerEvent tg_event
Definition: trigger.h:34
TupleTableSlot * tg_trigslot
Definition: trigger.h:39
TupleTableSlot * tg_newslot
Definition: trigger.h:40
Trigger * tg_trigger
Definition: trigger.h:38
Oid tgconstraint
Definition: reltrigger.h:35
Oid tgconstrrelid
Definition: reltrigger.h:33
char * tgname
Definition: reltrigger.h:27
TupleDesc tts_tupleDescriptor
Definition: tuptable.h:123
bool * tts_isnull
Definition: tuptable.h:127
Datum * tts_values
Definition: tuptable.h:125
dlist_node * cur
Definition: ilist.h:200
Definition: c.h:730
#define MinTransactionIdAttributeNumber
Definition: sysattr.h:22
#define FirstLowInvalidHeapAttributeNumber
Definition: sysattr.h:27
void ReleaseSysCache(HeapTuple tuple)
Definition: syscache.c:868
HeapTuple SearchSysCache1(int cacheId, Datum key1)
Definition: syscache.c:820
@ COLLOID
Definition: syscache.h:50
@ CONSTROID
Definition: syscache.h:53
#define GetSysCacheHashValue1(cacheId, key1)
Definition: syscache.h:209
void table_close(Relation relation, LOCKMODE lockmode)
Definition: table.c:126
Relation table_open(Oid relationId, LOCKMODE lockmode)
Definition: table.c:40
static bool table_tuple_satisfies_snapshot(Relation rel, TupleTableSlot *slot, Snapshot snapshot)
Definition: tableam.h:1330
#define RI_TRIGGER_FK
Definition: trigger.h:283
#define TRIGGER_FIRED_BY_DELETE(event)
Definition: trigger.h:113
#define CALLED_AS_TRIGGER(fcinfo)
Definition: trigger.h:26
#define TRIGGER_FIRED_FOR_ROW(event)
Definition: trigger.h:122
#define RI_TRIGGER_NONE
Definition: trigger.h:284
#define TRIGGER_FIRED_AFTER(event)
Definition: trigger.h:131
#define TRIGGER_FIRED_BY_INSERT(event)
Definition: trigger.h:110
#define TRIGGER_FIRED_BY_UPDATE(event)
Definition: trigger.h:116
#define RI_TRIGGER_PK
Definition: trigger.h:282
#define TupleDescAttr(tupdesc, i)
Definition: tupdesc.h:92
static Datum slot_getsysattr(TupleTableSlot *slot, int attnum, bool *isnull)
Definition: tuptable.h:409
static Datum slot_getattr(TupleTableSlot *slot, int attnum, bool *isnull)
Definition: tuptable.h:388
static bool slot_attisnull(TupleTableSlot *slot, int attnum)
Definition: tuptable.h:374
const char * name
void CommandCounterIncrement(void)
Definition: xact.c:1078
bool TransactionIdIsCurrentTransactionId(TransactionId xid)
Definition: xact.c:926
#define IsolationUsesXactSnapshot()
Definition: xact.h:51