Age Owner Branch data TLA Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * execIndexing.c
4 : : * routines for inserting index tuples and enforcing unique and
5 : : * exclusion constraints.
6 : : *
7 : : * ExecInsertIndexTuples() is the main entry point. It's called after
8 : : * inserting a tuple to the heap, and it inserts corresponding index tuples
9 : : * into all indexes. At the same time, it enforces any unique and
10 : : * exclusion constraints:
11 : : *
12 : : * Unique Indexes
13 : : * --------------
14 : : *
15 : : * Enforcing a unique constraint is straightforward. When the index AM
16 : : * inserts the tuple to the index, it also checks that there are no
17 : : * conflicting tuples in the index already. It does so atomically, so that
18 : : * even if two backends try to insert the same key concurrently, only one
19 : : * of them will succeed. All the logic to ensure atomicity, and to wait
20 : : * for in-progress transactions to finish, is handled by the index AM.
21 : : *
22 : : * If a unique constraint is deferred, we request the index AM to not
23 : : * throw an error if a conflict is found. Instead, we make note that there
24 : : * was a conflict and return the list of indexes with conflicts to the
25 : : * caller. The caller must re-check them later, by calling index_insert()
26 : : * with the UNIQUE_CHECK_EXISTING option.
27 : : *
28 : : * Exclusion Constraints
29 : : * ---------------------
30 : : *
31 : : * Exclusion constraints are different from unique indexes in that when the
32 : : * tuple is inserted to the index, the index AM does not check for
33 : : * duplicate keys at the same time. After the insertion, we perform a
34 : : * separate scan on the index to check for conflicting tuples, and if one
35 : : * is found, we throw an error and the transaction is aborted. If the
36 : : * conflicting tuple's inserter or deleter is in-progress, we wait for it
37 : : * to finish first.
38 : : *
39 : : * There is a chance of deadlock, if two backends insert a tuple at the
40 : : * same time, and then perform the scan to check for conflicts. They will
41 : : * find each other's tuple, and both try to wait for each other. The
42 : : * deadlock detector will detect that, and abort one of the transactions.
43 : : * That's fairly harmless, as one of them was bound to abort with a
44 : : * "duplicate key error" anyway, although you get a different error
45 : : * message.
46 : : *
47 : : * If an exclusion constraint is deferred, we still perform the conflict
48 : : * checking scan immediately after inserting the index tuple. But instead
49 : : * of throwing an error if a conflict is found, we return that information
50 : : * to the caller. The caller must re-check them later by calling
51 : : * check_exclusion_constraint().
52 : : *
53 : : * Speculative insertion
54 : : * ---------------------
55 : : *
56 : : * Speculative insertion is a two-phase mechanism used to implement
57 : : * INSERT ... ON CONFLICT. The tuple is first inserted into the heap
58 : : * and the indexes are updated as usual, but if a constraint is violated,
59 : : * we can still back out of the insertion without aborting the whole
60 : : * transaction. In an INSERT ... ON CONFLICT statement, if a conflict is
61 : : * detected, the inserted tuple is backed out and the ON CONFLICT action is
62 : : * executed instead.
63 : : *
64 : : * Insertion to a unique index works as usual: the index AM checks for
65 : : * duplicate keys atomically with the insertion. But instead of throwing
66 : : * an error on a conflict, the speculatively inserted heap tuple is backed
67 : : * out.
68 : : *
69 : : * Exclusion constraints are slightly more complicated. As mentioned
70 : : * earlier, there is a risk of deadlock when two backends insert the same
71 : : * key concurrently. That was not a problem for regular insertions, when
72 : : * one of the transactions has to be aborted anyway, but with a speculative
73 : : * insertion we cannot let a deadlock happen, because we only want to back
74 : : * out the speculatively inserted tuple on conflict, not abort the whole
75 : : * transaction.
76 : : *
77 : : * When a backend detects that the speculative insertion conflicts with
78 : : * another in-progress tuple, it has two options:
79 : : *
80 : : * 1. back out the speculatively inserted tuple, then wait for the other
81 : : * transaction, and retry. Or,
82 : : * 2. wait for the other transaction, with the speculatively inserted tuple
83 : : * still in place.
84 : : *
85 : : * If two backends insert at the same time, and both try to wait for each
86 : : * other, they will deadlock. So option 2 is not acceptable. Option 1
87 : : * avoids the deadlock, but it is prone to a livelock instead. Both
88 : : * transactions will wake up immediately as the other transaction backs
89 : : * out. Then they both retry, and conflict with each other again, lather,
90 : : * rinse, repeat.
91 : : *
92 : : * To avoid the livelock, one of the backends must back out first, and then
93 : : * wait, while the other one waits without backing out. It doesn't matter
94 : : * which one backs out, so we employ an arbitrary rule that the transaction
95 : : * with the higher XID backs out.
96 : : *
97 : : *
98 : : * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
99 : : * Portions Copyright (c) 1994, Regents of the University of California
100 : : *
101 : : *
102 : : * IDENTIFICATION
103 : : * src/backend/executor/execIndexing.c
104 : : *
105 : : *-------------------------------------------------------------------------
106 : : */
107 : : #include "postgres.h"
108 : :
109 : : #include "access/genam.h"
110 : : #include "access/relscan.h"
111 : : #include "access/tableam.h"
112 : : #include "access/xact.h"
113 : : #include "catalog/index.h"
114 : : #include "executor/executor.h"
115 : : #include "nodes/nodeFuncs.h"
116 : : #include "storage/lmgr.h"
117 : : #include "utils/injection_point.h"
118 : : #include "utils/lsyscache.h"
119 : : #include "utils/multirangetypes.h"
120 : : #include "utils/rangetypes.h"
121 : : #include "utils/snapmgr.h"
122 : :
123 : : /* waitMode argument to check_exclusion_or_unique_constraint() */
124 : : typedef enum
125 : : {
126 : : CEOUC_WAIT,
127 : : CEOUC_NOWAIT,
128 : : CEOUC_LIVELOCK_PREVENTING_WAIT,
129 : : } CEOUC_WAIT_MODE;
130 : :
131 : : static bool check_exclusion_or_unique_constraint(Relation heap, Relation index,
132 : : IndexInfo *indexInfo,
133 : : const ItemPointerData *tupleid,
134 : : const Datum *values, const bool *isnull,
135 : : EState *estate, bool newIndex,
136 : : CEOUC_WAIT_MODE waitMode,
137 : : bool violationOK,
138 : : ItemPointer conflictTid);
139 : :
140 : : static bool index_recheck_constraint(Relation index, const Oid *constr_procs,
141 : : const Datum *existing_values, const bool *existing_isnull,
142 : : const Datum *new_values);
143 : : static bool index_unchanged_by_update(ResultRelInfo *resultRelInfo,
144 : : EState *estate, IndexInfo *indexInfo,
145 : : Relation indexRelation);
146 : : static bool index_expression_changed_walker(Node *node,
147 : : Bitmapset *allUpdatedCols);
148 : : static void ExecWithoutOverlapsNotEmpty(Relation rel, NameData attname, Datum attval,
149 : : char typtype, Oid atttypid);
150 : :
151 : : /* ----------------------------------------------------------------
152 : : * ExecOpenIndices
153 : : *
154 : : * Find the indices associated with a result relation, open them,
155 : : * and save information about them in the result ResultRelInfo.
156 : : *
157 : : * At entry, caller has already opened and locked
158 : : * resultRelInfo->ri_RelationDesc.
159 : : * ----------------------------------------------------------------
160 : : */
161 : : void
4015 andres@anarazel.de 162 :CBC 1227254 : ExecOpenIndices(ResultRelInfo *resultRelInfo, bool speculative)
163 : : {
4029 heikki.linnakangas@i 164 : 1227254 : Relation resultRelation = resultRelInfo->ri_RelationDesc;
165 : : List *indexoidlist;
166 : : ListCell *l;
167 : : int len,
168 : : i;
169 : : RelationPtr relationDescs;
170 : : IndexInfo **indexInfoArray;
171 : :
172 : 1227254 : resultRelInfo->ri_NumIndices = 0;
173 : :
174 : : /* fast path if no indexes */
175 [ + + ]: 1227254 : if (!RelationGetForm(resultRelation)->relhasindex)
176 : 49896 : return;
177 : :
178 : : /*
179 : : * Get cached list of index OIDs
180 : : */
181 : 1177358 : indexoidlist = RelationGetIndexList(resultRelation);
182 : 1177358 : len = list_length(indexoidlist);
183 [ + + ]: 1177358 : if (len == 0)
184 : 20389 : return;
185 : :
186 : : /* This Assert will fail if ExecOpenIndices is called twice */
440 tgl@sss.pgh.pa.us 187 [ - + ]: 1156969 : Assert(resultRelInfo->ri_IndexRelationDescs == NULL);
188 : :
189 : : /*
190 : : * allocate space for result arrays
191 : : */
146 michael@paquier.xyz 192 :GNC 1156969 : relationDescs = palloc_array(Relation, len);
193 : 1156969 : indexInfoArray = palloc_array(IndexInfo *, len);
194 : :
4029 heikki.linnakangas@i 195 :CBC 1156969 : resultRelInfo->ri_NumIndices = len;
196 : 1156969 : resultRelInfo->ri_IndexRelationDescs = relationDescs;
197 : 1156969 : resultRelInfo->ri_IndexRelationInfo = indexInfoArray;
198 : :
199 : : /*
200 : : * For each index, open the index relation and save pg_index info. We
201 : : * acquire RowExclusiveLock, signifying we will update the index.
202 : : *
203 : : * Note: we do this even if the index is not indisready; it's not worth
204 : : * the trouble to optimize for the case where it isn't.
205 : : */
206 : 1156969 : i = 0;
207 [ + - + + : 3508480 : foreach(l, indexoidlist)
+ + ]
208 : : {
209 : 2351511 : Oid indexOid = lfirst_oid(l);
210 : : Relation indexDesc;
211 : : IndexInfo *ii;
212 : :
213 : 2351511 : indexDesc = index_open(indexOid, RowExclusiveLock);
214 : :
215 : : /* extract index key information from the index's pg_index info */
216 : 2351511 : ii = BuildIndexInfo(indexDesc);
217 : :
218 : : /*
219 : : * If the indexes are to be used for speculative insertion, add extra
220 : : * information required by unique index entries.
221 : : */
595 peter@eisentraut.org 222 [ + + + + : 2351511 : if (speculative && ii->ii_Unique && !indexDesc->rd_index->indisexclusion)
+ + ]
4015 andres@anarazel.de 223 : 1125 : BuildSpeculativeIndexInfo(indexDesc, ii);
224 : :
4029 heikki.linnakangas@i 225 : 2351511 : relationDescs[i] = indexDesc;
226 : 2351511 : indexInfoArray[i] = ii;
227 : 2351511 : i++;
228 : : }
229 : :
230 : 1156969 : list_free(indexoidlist);
231 : : }
232 : :
233 : : /* ----------------------------------------------------------------
234 : : * ExecCloseIndices
235 : : *
236 : : * Close the index relations stored in resultRelInfo
237 : : * ----------------------------------------------------------------
238 : : */
239 : : void
240 : 1274935 : ExecCloseIndices(ResultRelInfo *resultRelInfo)
241 : : {
242 : : int i;
243 : : int numIndices;
244 : : RelationPtr indexDescs;
245 : : IndexInfo **indexInfos;
246 : :
247 : 1274935 : numIndices = resultRelInfo->ri_NumIndices;
248 : 1274935 : indexDescs = resultRelInfo->ri_IndexRelationDescs;
892 tomas.vondra@postgre 249 : 1274935 : indexInfos = resultRelInfo->ri_IndexRelationInfo;
250 : :
4029 heikki.linnakangas@i 251 [ + + ]: 3625047 : for (i = 0; i < numIndices; i++)
252 : : {
253 : : /* This Assert will fail if ExecCloseIndices is called twice */
440 tgl@sss.pgh.pa.us 254 [ - + ]: 2350112 : Assert(indexDescs[i] != NULL);
255 : :
256 : : /* Give the index a chance to do some post-insert cleanup */
892 tomas.vondra@postgre 257 : 2350112 : index_insert_cleanup(indexDescs[i], indexInfos[i]);
258 : :
259 : : /* Drop lock acquired by ExecOpenIndices */
4029 heikki.linnakangas@i 260 : 2350112 : index_close(indexDescs[i], RowExclusiveLock);
261 : :
262 : : /* Mark the index as closed */
440 tgl@sss.pgh.pa.us 263 : 2350112 : indexDescs[i] = NULL;
264 : : }
265 : :
266 : : /*
267 : : * We don't attempt to free the IndexInfo data structures or the arrays,
268 : : * instead assuming that such stuff will be cleaned up automatically in
269 : : * FreeExecutorState.
270 : : */
4029 heikki.linnakangas@i 271 : 1274935 : }
272 : :
273 : : /* ----------------------------------------------------------------
274 : : * ExecInsertIndexTuples
275 : : *
276 : : * This routine takes care of inserting index tuples
277 : : * into all the relations indexing the result relation
278 : : * when a heap tuple is inserted into the result relation.
279 : : *
280 : : * When EIIT_IS_UPDATE is set and EIIT_ONLY_SUMMARIZING isn't,
281 : : * executor is performing an UPDATE that could not use an
282 : : * optimization like heapam's HOT (in more general terms a
283 : : * call to table_tuple_update() took place and set
284 : : * 'update_indexes' to TU_All). Receiving this hint makes
285 : : * us consider if we should pass down the 'indexUnchanged'
286 : : * hint in turn. That's something that we figure out for
287 : : * each index_insert() call iff EIIT_IS_UPDATE is set.
288 : : * (When that flag is not set we already know not to pass the
289 : : * hint to any index.)
290 : : *
291 : : * If EIIT_ONLY_SUMMARIZING is set, an equivalent optimization to
292 : : * HOT has been applied and any updated columns are indexed
293 : : * only by summarizing indexes (or in more general terms a
294 : : * call to table_tuple_update() took place and set
295 : : * 'update_indexes' to TU_Summarizing). We can (and must)
296 : : * therefore only update the indexes that have
297 : : * 'amsummarizing' = true.
298 : : *
299 : : * Unique and exclusion constraints are enforced at the same
300 : : * time. This returns a list of index OIDs for any unique or
301 : : * exclusion constraints that are deferred and that had
302 : : * potential (unconfirmed) conflicts. (if EIIT_NO_DUPE_ERROR,
303 : : * the same is done for non-deferred constraints, but report
304 : : * if conflict was speculative or deferred conflict to caller)
305 : : *
306 : : * If 'arbiterIndexes' is nonempty, EIIT_NO_DUPE_ERROR applies only to
307 : : * those indexes. NIL means EIIT_NO_DUPE_ERROR applies to all indexes.
308 : : * ----------------------------------------------------------------
309 : : */
310 : : List *
2029 311 : 2826575 : ExecInsertIndexTuples(ResultRelInfo *resultRelInfo,
312 : : EState *estate,
313 : : uint32 flags,
314 : : TupleTableSlot *slot,
315 : : List *arbiterIndexes,
316 : : bool *specConflict)
317 : : {
2600 andres@anarazel.de 318 : 2826575 : ItemPointer tupleid = &slot->tts_tid;
4029 heikki.linnakangas@i 319 : 2826575 : List *result = NIL;
320 : : int i;
321 : : int numIndices;
322 : : RelationPtr relationDescs;
323 : : Relation heapRelation;
324 : : IndexInfo **indexInfoArray;
325 : : ExprContext *econtext;
326 : : Datum values[INDEX_MAX_KEYS];
327 : : bool isnull[INDEX_MAX_KEYS];
328 : :
2600 andres@anarazel.de 329 [ - + ]: 2826575 : Assert(ItemPointerIsValid(tupleid));
330 : :
331 : : /*
332 : : * Get information from the result relation info structure.
333 : : */
4029 heikki.linnakangas@i 334 : 2826575 : numIndices = resultRelInfo->ri_NumIndices;
335 : 2826575 : relationDescs = resultRelInfo->ri_IndexRelationDescs;
336 : 2826575 : indexInfoArray = resultRelInfo->ri_IndexRelationInfo;
337 : 2826575 : heapRelation = resultRelInfo->ri_RelationDesc;
338 : :
339 : : /* Sanity check: slot must belong to the same rel as the resultRelInfo. */
2526 drowley@postgresql.o 340 [ - + ]: 2826575 : Assert(slot->tts_tableOid == RelationGetRelid(heapRelation));
341 : :
342 : : /*
343 : : * We will use the EState's per-tuple context for evaluating predicates
344 : : * and index expressions (creating it if it's not already there).
345 : : */
4029 heikki.linnakangas@i 346 [ + + ]: 2826575 : econtext = GetPerTupleExprContext(estate);
347 : :
348 : : /* Arrange for econtext's scan tuple to be the tuple under test */
349 : 2826575 : econtext->ecxt_scantuple = slot;
350 : :
351 : : /*
352 : : * for each index, form and insert the index tuple
353 : : */
354 [ + + ]: 5952380 : for (i = 0; i < numIndices; i++)
355 : : {
356 : 3126259 : Relation indexRelation = relationDescs[i];
357 : : IndexInfo *indexInfo;
358 : : bool applyNoDupErr;
359 : : IndexUniqueCheck checkUnique;
360 : : bool indexUnchanged;
361 : : bool satisfiesConstraint;
362 : :
363 [ - + ]: 3126259 : if (indexRelation == NULL)
4029 heikki.linnakangas@i 364 :UBC 0 : continue;
365 : :
4029 heikki.linnakangas@i 366 :CBC 3126259 : indexInfo = indexInfoArray[i];
367 : :
368 : : /* If the index is marked as read-only, ignore it */
369 [ + + ]: 3126259 : if (!indexInfo->ii_ReadyForInserts)
370 : 99 : continue;
371 : :
372 : : /*
373 : : * Skip processing of non-summarizing indexes if we only update
374 : : * summarizing indexes
375 : : */
77 alvherre@kurilemu.de 376 [ + + + + ]:GNC 3126160 : if ((flags & EIIT_ONLY_SUMMARIZING) && !indexInfo->ii_Summarizing)
1142 tomas.vondra@postgre 377 :CBC 4 : continue;
378 : :
379 : : /* Check for partial index */
4029 heikki.linnakangas@i 380 [ + + ]: 3126156 : if (indexInfo->ii_Predicate != NIL)
381 : : {
382 : : ExprState *predicate;
383 : :
384 : : /*
385 : : * If predicate state not set up yet, create it (in the estate's
386 : : * per-query context)
387 : : */
388 : 200568 : predicate = indexInfo->ii_PredicateState;
3339 andres@anarazel.de 389 [ + + ]: 200568 : if (predicate == NULL)
390 : : {
391 : 149 : predicate = ExecPrepareQual(indexInfo->ii_Predicate, estate);
4029 heikki.linnakangas@i 392 : 149 : indexInfo->ii_PredicateState = predicate;
393 : : }
394 : :
395 : : /* Skip this index-update if the predicate isn't satisfied */
3339 andres@anarazel.de 396 [ + + ]: 200568 : if (!ExecQual(predicate, econtext))
4029 heikki.linnakangas@i 397 : 200286 : continue;
398 : : }
399 : :
400 : : /*
401 : : * FormIndexDatum fills in its values and isnull parameters with the
402 : : * appropriate values for the column(s) of the index.
403 : : */
404 : 2925870 : FormIndexDatum(indexInfo,
405 : : slot,
406 : : estate,
407 : : values,
408 : : isnull);
409 : :
410 : : /* Check whether to apply noDupErr to this index */
77 alvherre@kurilemu.de 411 [ + + + + ]:GNC 3024173 : applyNoDupErr = (flags & EIIT_NO_DUPE_ERROR) &&
3592 tgl@sss.pgh.pa.us 412 [ + + ]:CBC 98303 : (arbiterIndexes == NIL ||
413 : 98303 : list_member_oid(arbiterIndexes,
414 : 98303 : indexRelation->rd_index->indexrelid));
415 : :
416 : : /*
417 : : * The index AM does the actual insertion, plus uniqueness checking.
418 : : *
419 : : * For an immediate-mode unique index, we just tell the index AM to
420 : : * throw error if not unique.
421 : : *
422 : : * For a deferrable unique index, we tell the index AM to just detect
423 : : * possible non-uniqueness, and we add the index OID to the result
424 : : * list if further checking is needed.
425 : : *
426 : : * For a speculative insertion (used by INSERT ... ON CONFLICT), do
427 : : * the same as for a deferrable unique index.
428 : : */
4029 heikki.linnakangas@i 429 [ + + ]: 2925870 : if (!indexRelation->rd_index->indisunique)
430 : 1527986 : checkUnique = UNIQUE_CHECK_NO;
3592 tgl@sss.pgh.pa.us 431 [ + + ]: 1397884 : else if (applyNoDupErr)
4015 andres@anarazel.de 432 : 98351 : checkUnique = UNIQUE_CHECK_PARTIAL;
4029 heikki.linnakangas@i 433 [ + + ]: 1299533 : else if (indexRelation->rd_index->indimmediate)
434 : 1299434 : checkUnique = UNIQUE_CHECK_YES;
435 : : else
436 : 99 : checkUnique = UNIQUE_CHECK_PARTIAL;
437 : :
438 : : /*
439 : : * There's definitely going to be an index_insert() call for this
440 : : * index. If we're being called as part of an UPDATE statement,
441 : : * consider if the 'indexUnchanged' = true hint should be passed.
442 : : */
77 alvherre@kurilemu.de 443 [ + + + + ]:GNC 3210026 : indexUnchanged = ((flags & EIIT_IS_UPDATE) &&
444 : 284156 : index_unchanged_by_update(resultRelInfo,
445 : : estate,
446 : : indexInfo,
447 : : indexRelation));
448 : :
449 : : satisfiesConstraint =
4029 heikki.linnakangas@i 450 :CBC 2925870 : index_insert(indexRelation, /* index relation */
451 : : values, /* array of index Datums */
452 : : isnull, /* null flags */
453 : : tupleid, /* tid of heap tuple */
454 : : heapRelation, /* heap relation */
455 : : checkUnique, /* type of uniqueness check to do */
456 : : indexUnchanged, /* UPDATE without logical change? */
457 : : indexInfo); /* index AM may need this */
458 : :
459 : : /*
460 : : * If the index has an associated exclusion constraint, check that.
461 : : * This is simpler than the process for uniqueness checks since we
462 : : * always insert first and then check. If the constraint is deferred,
463 : : * we check now anyway, but don't throw error on violation or wait for
464 : : * a conclusive outcome from a concurrent insertion; instead we'll
465 : : * queue a recheck event. Similarly, noDupErr callers (speculative
466 : : * inserters) will recheck later, and wait for a conclusive outcome
467 : : * then.
468 : : *
469 : : * An index for an exclusion constraint can't also be UNIQUE (not an
470 : : * essential property, we just don't allow it in the grammar), so no
471 : : * need to preserve the prior state of satisfiesConstraint.
472 : : */
473 [ + + ]: 2925547 : if (indexInfo->ii_ExclusionOps != NULL)
474 : : {
475 : : bool violationOK;
476 : : CEOUC_WAIT_MODE waitMode;
477 : :
3592 tgl@sss.pgh.pa.us 478 [ + + ]: 2892 : if (applyNoDupErr)
479 : : {
4015 andres@anarazel.de 480 : 108 : violationOK = true;
481 : 108 : waitMode = CEOUC_LIVELOCK_PREVENTING_WAIT;
482 : : }
483 [ + + ]: 2784 : else if (!indexRelation->rd_index->indimmediate)
484 : : {
485 : 28 : violationOK = true;
486 : 28 : waitMode = CEOUC_NOWAIT;
487 : : }
488 : : else
489 : : {
490 : 2756 : violationOK = false;
491 : 2756 : waitMode = CEOUC_WAIT;
492 : : }
493 : :
494 : : satisfiesConstraint =
495 : 2892 : check_exclusion_or_unique_constraint(heapRelation,
496 : : indexRelation, indexInfo,
497 : : tupleid, values, isnull,
498 : : estate, false,
499 : : waitMode, violationOK, NULL);
500 : : }
501 : :
4029 heikki.linnakangas@i 502 [ + + ]: 2925416 : if ((checkUnique == UNIQUE_CHECK_PARTIAL ||
503 [ + + ]: 2826966 : indexInfo->ii_ExclusionOps != NULL) &&
504 [ + + ]: 101103 : !satisfiesConstraint)
505 : : {
506 : : /*
507 : : * The tuple potentially violates the uniqueness or exclusion
508 : : * constraint, so make a note of the index so that we can re-check
509 : : * it later. Speculative inserters are told if there was a
510 : : * speculative conflict, since that always requires a restart.
511 : : */
512 : 164 : result = lappend_oid(result, RelationGetRelid(indexRelation));
4015 andres@anarazel.de 513 [ + + + - ]: 164 : if (indexRelation->rd_index->indimmediate && specConflict)
514 : 83 : *specConflict = true;
515 : : }
516 : : }
517 : :
4029 heikki.linnakangas@i 518 : 2826121 : return result;
519 : : }
520 : :
521 : : /* ----------------------------------------------------------------
522 : : * ExecCheckIndexConstraints
523 : : *
524 : : * This routine checks if a tuple violates any unique or
525 : : * exclusion constraints. Returns true if there is no conflict.
526 : : * Otherwise returns false, and the TID of the conflicting
527 : : * tuple is returned in *conflictTid.
528 : : *
529 : : * If 'arbiterIndexes' is given, only those indexes are checked.
530 : : * NIL means all indexes.
531 : : *
532 : : * Note that this doesn't lock the values in any way, so it's
533 : : * possible that a conflicting tuple is inserted immediately
534 : : * after this returns. This can be used for either a pre-check
535 : : * before insertion or a re-check after finding a conflict.
536 : : *
537 : : * 'tupleid' should be the TID of the tuple that has been recently
538 : : * inserted (or can be invalid if we haven't inserted a new tuple yet).
539 : : * This tuple will be excluded from conflict checking.
540 : : * ----------------------------------------------------------------
541 : : */
542 : : bool
2029 543 : 5390 : ExecCheckIndexConstraints(ResultRelInfo *resultRelInfo, TupleTableSlot *slot,
544 : : EState *estate, ItemPointer conflictTid,
545 : : const ItemPointerData *tupleid, List *arbiterIndexes)
546 : : {
547 : : int i;
548 : : int numIndices;
549 : : RelationPtr relationDescs;
550 : : Relation heapRelation;
551 : : IndexInfo **indexInfoArray;
552 : : ExprContext *econtext;
553 : : Datum values[INDEX_MAX_KEYS];
554 : : bool isnull[INDEX_MAX_KEYS];
555 : : ItemPointerData invalidItemPtr;
4015 andres@anarazel.de 556 : 5390 : bool checkedIndex = false;
557 : :
558 : 5390 : ItemPointerSetInvalid(conflictTid);
559 : 5390 : ItemPointerSetInvalid(&invalidItemPtr);
560 : :
561 : : /*
562 : : * Get information from the result relation info structure.
563 : : */
564 : 5390 : numIndices = resultRelInfo->ri_NumIndices;
565 : 5390 : relationDescs = resultRelInfo->ri_IndexRelationDescs;
566 : 5390 : indexInfoArray = resultRelInfo->ri_IndexRelationInfo;
567 : 5390 : heapRelation = resultRelInfo->ri_RelationDesc;
568 : :
569 : : /*
570 : : * We will use the EState's per-tuple context for evaluating predicates
571 : : * and index expressions (creating it if it's not already there).
572 : : */
573 [ + + ]: 5390 : econtext = GetPerTupleExprContext(estate);
574 : :
575 : : /* Arrange for econtext's scan tuple to be the tuple under test */
576 : 5390 : econtext->ecxt_scantuple = slot;
577 : :
578 : : /*
579 : : * For each index, form index tuple and check if it satisfies the
580 : : * constraint.
581 : : */
582 [ + + ]: 7732 : for (i = 0; i < numIndices; i++)
583 : : {
584 : 5501 : Relation indexRelation = relationDescs[i];
585 : : IndexInfo *indexInfo;
586 : : bool satisfiesConstraint;
587 : :
588 [ - + ]: 5501 : if (indexRelation == NULL)
4015 andres@anarazel.de 589 :UBC 0 : continue;
590 : :
4015 andres@anarazel.de 591 :CBC 5501 : indexInfo = indexInfoArray[i];
592 : :
593 [ + + + + ]: 5501 : if (!indexInfo->ii_Unique && !indexInfo->ii_ExclusionOps)
594 : 2 : continue;
595 : :
596 : : /* If the index is marked as read-only, ignore it */
597 [ - + ]: 5499 : if (!indexInfo->ii_ReadyForInserts)
4015 andres@anarazel.de 598 :UBC 0 : continue;
599 : :
600 : : /* When specific arbiter indexes requested, only examine them */
4015 andres@anarazel.de 601 [ + + ]:CBC 5499 : if (arbiterIndexes != NIL &&
602 [ + + ]: 5337 : !list_member_oid(arbiterIndexes,
603 : 5337 : indexRelation->rd_index->indexrelid))
604 : 83 : continue;
605 : :
606 [ + + ]: 5416 : if (!indexRelation->rd_index->indimmediate)
607 [ + - ]: 4 : ereport(ERROR,
608 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
609 : : errmsg("ON CONFLICT does not support deferrable unique constraints/exclusion constraints as arbiters"),
610 : : errtableconstraint(heapRelation,
611 : : RelationGetRelationName(indexRelation))));
612 : :
613 : 5412 : checkedIndex = true;
614 : :
615 : : /* Check for partial index */
616 [ + + ]: 5412 : if (indexInfo->ii_Predicate != NIL)
617 : : {
618 : : ExprState *predicate;
619 : :
620 : : /*
621 : : * If predicate state not set up yet, create it (in the estate's
622 : : * per-query context)
623 : : */
624 : 26 : predicate = indexInfo->ii_PredicateState;
3339 625 [ + - ]: 26 : if (predicate == NULL)
626 : : {
627 : 26 : predicate = ExecPrepareQual(indexInfo->ii_Predicate, estate);
4015 628 : 26 : indexInfo->ii_PredicateState = predicate;
629 : : }
630 : :
631 : : /* Skip this index-update if the predicate isn't satisfied */
3339 632 [ - + ]: 26 : if (!ExecQual(predicate, econtext))
4015 andres@anarazel.de 633 :UBC 0 : continue;
634 : : }
635 : :
636 : : /*
637 : : * FormIndexDatum fills in its values and isnull parameters with the
638 : : * appropriate values for the column(s) of the index.
639 : : */
4015 andres@anarazel.de 640 :CBC 5412 : FormIndexDatum(indexInfo,
641 : : slot,
642 : : estate,
643 : : values,
644 : : isnull);
645 : :
646 : : satisfiesConstraint =
647 : 5412 : check_exclusion_or_unique_constraint(heapRelation, indexRelation,
648 : : indexInfo, tupleid,
649 : : values, isnull, estate, false,
650 : : CEOUC_WAIT, true,
651 : : conflictTid);
652 [ + + ]: 5411 : if (!satisfiesConstraint)
653 : 3154 : return false;
654 : : }
655 : :
656 [ + + - + ]: 2231 : if (arbiterIndexes != NIL && !checkedIndex)
4015 andres@anarazel.de 657 [ # # ]:UBC 0 : elog(ERROR, "unexpected failure to find arbiter index");
658 : :
4015 andres@anarazel.de 659 :CBC 2231 : return true;
660 : : }
661 : :
662 : : /*
663 : : * Check for violation of an exclusion or unique constraint
664 : : *
665 : : * heap: the table containing the new tuple
666 : : * index: the index supporting the constraint
667 : : * indexInfo: info about the index, including the exclusion properties
668 : : * tupleid: heap TID of the new tuple we have just inserted (invalid if we
669 : : * haven't inserted a new tuple yet)
670 : : * values, isnull: the *index* column values computed for the new tuple
671 : : * estate: an EState we can do evaluation in
672 : : * newIndex: if true, we are trying to build a new index (this affects
673 : : * only the wording of error messages)
674 : : * waitMode: whether to wait for concurrent inserters/deleters
675 : : * violationOK: if true, don't throw error for violation
676 : : * conflictTid: if not-NULL, the TID of the conflicting tuple is returned here
677 : : *
678 : : * Returns true if OK, false if actual or potential violation
679 : : *
680 : : * 'waitMode' determines what happens if a conflict is detected with a tuple
681 : : * that was inserted or deleted by a transaction that's still running.
682 : : * CEOUC_WAIT means that we wait for the transaction to commit, before
683 : : * throwing an error or returning. CEOUC_NOWAIT means that we report the
684 : : * violation immediately; so the violation is only potential, and the caller
685 : : * must recheck sometime later. This behavior is convenient for deferred
686 : : * exclusion checks; we need not bother queuing a deferred event if there is
687 : : * definitely no conflict at insertion time.
688 : : *
689 : : * CEOUC_LIVELOCK_PREVENTING_WAIT is like CEOUC_NOWAIT, but we will sometimes
690 : : * wait anyway, to prevent livelocking if two transactions try inserting at
691 : : * the same time. This is used with speculative insertions, for INSERT ON
692 : : * CONFLICT statements. (See notes in file header)
693 : : *
694 : : * If violationOK is true, we just report the potential or actual violation to
695 : : * the caller by returning 'false'. Otherwise we throw a descriptive error
696 : : * message here. When violationOK is false, a false result is impossible.
697 : : *
698 : : * Note: The indexam is normally responsible for checking unique constraints,
699 : : * so this normally only needs to be used for exclusion constraints. But this
700 : : * function is also called when doing a "pre-check" for conflicts on a unique
701 : : * constraint, when doing speculative insertion. Caller may use the returned
702 : : * conflict TID to take further steps.
703 : : */
704 : : static bool
705 : 8622 : check_exclusion_or_unique_constraint(Relation heap, Relation index,
706 : : IndexInfo *indexInfo,
707 : : const ItemPointerData *tupleid,
708 : : const Datum *values, const bool *isnull,
709 : : EState *estate, bool newIndex,
710 : : CEOUC_WAIT_MODE waitMode,
711 : : bool violationOK,
712 : : ItemPointer conflictTid)
713 : : {
714 : : Oid *constr_procs;
715 : : uint16 *constr_strats;
4029 heikki.linnakangas@i 716 : 8622 : Oid *index_collations = index->rd_indcollation;
2950 teodor@sigaev.ru 717 : 8622 : int indnkeyatts = IndexRelationGetNumberOfKeyAttributes(index);
718 : : IndexScanDesc index_scan;
719 : : ScanKeyData scankeys[INDEX_MAX_KEYS];
720 : : SnapshotData DirtySnapshot;
721 : : int i;
722 : : bool conflict;
723 : : bool found_self;
724 : : ExprContext *econtext;
725 : : TupleTableSlot *existing_slot;
726 : : TupleTableSlot *save_scantuple;
727 : :
4015 andres@anarazel.de 728 [ + + ]: 8622 : if (indexInfo->ii_ExclusionOps)
729 : : {
730 : 3314 : constr_procs = indexInfo->ii_ExclusionProcs;
731 : 3314 : constr_strats = indexInfo->ii_ExclusionStrats;
732 : : }
733 : : else
734 : : {
735 : 5308 : constr_procs = indexInfo->ii_UniqueProcs;
736 : 5308 : constr_strats = indexInfo->ii_UniqueStrats;
737 : : }
738 : :
739 : : /*
740 : : * If this is a WITHOUT OVERLAPS constraint, we must also forbid empty
741 : : * ranges/multiranges. This must happen before we look for NULLs below, or
742 : : * a UNIQUE constraint could insert an empty range along with a NULL
743 : : * scalar part.
744 : : */
595 peter@eisentraut.org 745 [ + + ]: 8622 : if (indexInfo->ii_WithoutOverlaps)
746 : : {
747 : : /*
748 : : * Look up the type from the heap tuple, but check the Datum from the
749 : : * index tuple.
750 : : */
751 : 3049 : AttrNumber attno = indexInfo->ii_IndexAttrNumbers[indnkeyatts - 1];
752 : :
753 [ + + ]: 3049 : if (!isnull[indnkeyatts - 1])
754 : : {
755 : 3009 : TupleDesc tupdesc = RelationGetDescr(heap);
756 : 3009 : Form_pg_attribute att = TupleDescAttr(tupdesc, attno - 1);
28 tgl@sss.pgh.pa.us 757 : 3009 : TypeCacheEntry *typcache = lookup_type_cache(att->atttypid,
758 : : TYPECACHE_DOMAIN_BASE_INFO);
759 : : char typtype;
760 : :
761 [ + + ]: 3009 : if (OidIsValid(typcache->domainBaseType))
762 : 16 : typtype = get_typtype(typcache->domainBaseType);
763 : : else
764 : 2993 : typtype = typcache->typtype;
765 : :
595 peter@eisentraut.org 766 : 3009 : ExecWithoutOverlapsNotEmpty(heap, att->attname,
767 : 3009 : values[indnkeyatts - 1],
768 : : typtype, att->atttypid);
769 : : }
770 : : }
771 : :
772 : : /*
773 : : * If any of the input values are NULL, and the index uses the default
774 : : * nulls-are-distinct mode, the constraint check is assumed to pass (i.e.,
775 : : * we assume the operators are strict). Otherwise, we interpret the
776 : : * constraint as specifying IS NULL for each column whose input value is
777 : : * NULL.
778 : : */
1370 tgl@sss.pgh.pa.us 779 [ + + ]: 8566 : if (!indexInfo->ii_NullsNotDistinct)
780 : : {
781 [ + + ]: 20147 : for (i = 0; i < indnkeyatts; i++)
782 : : {
783 [ + + ]: 11665 : if (isnull[i])
784 : 80 : return true;
785 : : }
786 : : }
787 : :
788 : : /*
789 : : * Search the tuples that are in the index for any violations, including
790 : : * tuples that aren't visible yet.
791 : : */
4029 heikki.linnakangas@i 792 : 8486 : InitDirtySnapshot(DirtySnapshot);
793 : :
2950 teodor@sigaev.ru 794 [ + + ]: 20035 : for (i = 0; i < indnkeyatts; i++)
795 : : {
4029 heikki.linnakangas@i 796 : 11549 : ScanKeyEntryInitialize(&scankeys[i],
1370 tgl@sss.pgh.pa.us 797 : 11549 : isnull[i] ? SK_ISNULL | SK_SEARCHNULL : 0,
4029 heikki.linnakangas@i 798 : 11549 : i + 1,
799 : 11549 : constr_strats[i],
800 : : InvalidOid,
801 : 11549 : index_collations[i],
802 : 11549 : constr_procs[i],
803 [ + + ]: 11549 : values[i]);
804 : : }
805 : :
806 : : /*
807 : : * Need a TupleTableSlot to put existing tuples in.
808 : : *
809 : : * To use FormIndexDatum, we have to make the econtext's scantuple point
810 : : * to this slot. Be sure to save and restore caller's value for
811 : : * scantuple.
812 : : */
2612 andres@anarazel.de 813 : 8486 : existing_slot = table_slot_create(heap, NULL);
814 : :
4029 heikki.linnakangas@i 815 [ + - ]: 8486 : econtext = GetPerTupleExprContext(estate);
816 : 8486 : save_scantuple = econtext->ecxt_scantuple;
817 : 8486 : econtext->ecxt_scantuple = existing_slot;
818 : :
819 : : /*
820 : : * May have to restart scan from this point if a potential conflict is
821 : : * found.
822 : : */
823 : 8523 : retry:
824 : 8523 : conflict = false;
825 : 8523 : found_self = false;
36 melanieplageman@gmai 826 :GNC 8523 : index_scan = index_beginscan(heap, index,
827 : : &DirtySnapshot, NULL, indnkeyatts, 0,
828 : : SO_NONE);
2950 teodor@sigaev.ru 829 :CBC 8523 : index_rescan(index_scan, scankeys, indnkeyatts, NULL, 0);
830 : :
2612 andres@anarazel.de 831 [ + + ]: 11505 : while (index_getnext_slot(index_scan, ForwardScanDirection, existing_slot))
832 : : {
833 : : TransactionId xwait;
834 : : XLTW_Oper reason_wait;
835 : : Datum existing_values[INDEX_MAX_KEYS];
836 : : bool existing_isnull[INDEX_MAX_KEYS];
837 : : char *error_new;
838 : : char *error_existing;
839 : :
840 : : /*
841 : : * Ignore the entry for the tuple we're trying to check.
842 : : */
4015 843 [ + + + + ]: 9508 : if (ItemPointerIsValid(tupleid) &&
2612 844 : 3191 : ItemPointerEquals(tupleid, &existing_slot->tts_tid))
845 : : {
4029 heikki.linnakangas@i 846 [ - + ]: 2946 : if (found_self) /* should not happen */
4029 heikki.linnakangas@i 847 [ # # ]:UBC 0 : elog(ERROR, "found self tuple multiple times in index \"%s\"",
848 : : RelationGetRelationName(index));
4029 heikki.linnakangas@i 849 :CBC 2946 : found_self = true;
850 : 2982 : continue;
851 : : }
852 : :
853 : : /*
854 : : * Extract the index column values and isnull flags from the existing
855 : : * tuple.
856 : : */
857 : 3371 : FormIndexDatum(indexInfo, existing_slot, estate,
858 : : existing_values, existing_isnull);
859 : :
860 : : /* If lossy indexscan, must recheck the condition */
861 [ + + ]: 3371 : if (index_scan->xs_recheck)
862 : : {
863 [ + + ]: 92 : if (!index_recheck_constraint(index,
864 : : constr_procs,
865 : : existing_values,
866 : : existing_isnull,
867 : : values))
868 : 36 : continue; /* tuple doesn't actually match, so no
869 : : * conflict */
870 : : }
871 : :
872 : : /*
873 : : * At this point we have either a conflict or a potential conflict.
874 : : *
875 : : * If an in-progress transaction is affecting the visibility of this
876 : : * tuple, we need to wait for it to complete and then recheck (unless
877 : : * the caller requested not to). For simplicity we do rechecking by
878 : : * just restarting the whole scan --- this case probably doesn't
879 : : * happen often enough to be worth trying harder, and anyway we don't
880 : : * want to hold any index internal locks while waiting.
881 : : */
882 : 6670 : xwait = TransactionIdIsValid(DirtySnapshot.xmin) ?
883 [ + + ]: 3335 : DirtySnapshot.xmin : DirtySnapshot.xmax;
884 : :
4015 andres@anarazel.de 885 [ + + - + ]: 3335 : if (TransactionIdIsValid(xwait) &&
4015 andres@anarazel.de 886 [ # # ]:UBC 0 : (waitMode == CEOUC_WAIT ||
887 : 0 : (waitMode == CEOUC_LIVELOCK_PREVENTING_WAIT &&
888 [ # # # # ]: 0 : DirtySnapshot.speculativeToken &&
889 : 0 : TransactionIdPrecedes(GetCurrentTransactionId(), xwait))))
890 : : {
3703 sfrost@snowman.net 891 :CBC 76 : reason_wait = indexInfo->ii_ExclusionOps ?
892 [ - + ]: 38 : XLTW_RecheckExclusionConstr : XLTW_InsertIndex;
4029 heikki.linnakangas@i 893 : 38 : index_endscan(index_scan);
4015 andres@anarazel.de 894 [ + + ]: 38 : if (DirtySnapshot.speculativeToken)
895 : 1 : SpeculativeInsertionWait(DirtySnapshot.xmin,
896 : : DirtySnapshot.speculativeToken);
897 : : else
2612 898 : 37 : XactLockTableWait(xwait, heap,
2612 andres@anarazel.de 899 :GIC 37 : &existing_slot->tts_tid, reason_wait);
4029 heikki.linnakangas@i 900 :CBC 37 : goto retry;
901 : : }
902 : :
903 : : /*
904 : : * We have a definite conflict (or a potential one, but the caller
905 : : * didn't want to wait). Return it to caller, or report it.
906 : : */
4015 andres@anarazel.de 907 [ + + ]: 3297 : if (violationOK)
908 : : {
909 : 3170 : conflict = true;
910 [ + + ]: 3170 : if (conflictTid)
2612 911 : 3154 : *conflictTid = existing_slot->tts_tid;
4015 912 : 3170 : break;
913 : : }
914 : :
4029 heikki.linnakangas@i 915 : 127 : error_new = BuildIndexValueDescription(index, values, isnull);
916 : 127 : error_existing = BuildIndexValueDescription(index, existing_values,
917 : : existing_isnull);
918 [ + + ]: 127 : if (newIndex)
919 [ + - + - : 24 : ereport(ERROR,
+ - ]
920 : : (errcode(ERRCODE_EXCLUSION_VIOLATION),
921 : : errmsg("could not create exclusion constraint \"%s\"",
922 : : RelationGetRelationName(index)),
923 : : error_new && error_existing ?
924 : : errdetail("Key %s conflicts with key %s.",
925 : : error_new, error_existing) :
926 : : errdetail("Key conflicts exist."),
927 : : errtableconstraint(heap,
928 : : RelationGetRelationName(index))));
929 : : else
930 [ + - + - : 103 : ereport(ERROR,
+ - ]
931 : : (errcode(ERRCODE_EXCLUSION_VIOLATION),
932 : : errmsg("conflicting key value violates exclusion constraint \"%s\"",
933 : : RelationGetRelationName(index)),
934 : : error_new && error_existing ?
935 : : errdetail("Key %s conflicts with existing key %s.",
936 : : error_new, error_existing) :
937 : : errdetail("Key conflicts with existing key."),
938 : : errtableconstraint(heap,
939 : : RelationGetRelationName(index))));
940 : : }
941 : :
942 : 8358 : index_endscan(index_scan);
943 : :
944 : : /*
945 : : * Ordinarily, at this point the search should have found the originally
946 : : * inserted tuple (if any), unless we exited the loop early because of
947 : : * conflict. However, it is possible to define exclusion constraints for
948 : : * which that wouldn't be true --- for instance, if the operator is <>. So
949 : : * we no longer complain if found_self is still false.
950 : : */
951 : :
952 : 8358 : econtext->ecxt_scantuple = save_scantuple;
953 : :
954 : 8358 : ExecDropSingleTupleTableSlot(existing_slot);
955 : :
956 : : #ifdef USE_INJECTION_POINTS
161 alvherre@kurilemu.de 957 [ + + ]:GNC 8358 : if (!conflict)
162 958 : 5188 : INJECTION_POINT("check-exclusion-or-unique-constraint-no-conflict", NULL);
959 : : #endif
960 : :
4029 heikki.linnakangas@i 961 :CBC 8358 : return !conflict;
962 : : }
963 : :
964 : : /*
965 : : * Check for violation of an exclusion constraint
966 : : *
967 : : * This is a dumbed down version of check_exclusion_or_unique_constraint
968 : : * for external callers. They don't need all the special modes.
969 : : */
970 : : void
4015 andres@anarazel.de 971 : 318 : check_exclusion_constraint(Relation heap, Relation index,
972 : : IndexInfo *indexInfo,
973 : : const ItemPointerData *tupleid,
974 : : const Datum *values, const bool *isnull,
975 : : EState *estate, bool newIndex)
976 : : {
977 : 318 : (void) check_exclusion_or_unique_constraint(heap, index, indexInfo, tupleid,
978 : : values, isnull,
979 : : estate, newIndex,
980 : : CEOUC_WAIT, false, NULL);
981 : 266 : }
982 : :
983 : : /*
984 : : * Check existing tuple's index values to see if it really matches the
985 : : * exclusion condition against the new_values. Returns true if conflict.
986 : : */
987 : : static bool
938 peter@eisentraut.org 988 : 92 : index_recheck_constraint(Relation index, const Oid *constr_procs,
989 : : const Datum *existing_values, const bool *existing_isnull,
990 : : const Datum *new_values)
991 : : {
2950 teodor@sigaev.ru 992 : 92 : int indnkeyatts = IndexRelationGetNumberOfKeyAttributes(index);
993 : : int i;
994 : :
995 [ + + ]: 228 : for (i = 0; i < indnkeyatts; i++)
996 : : {
997 : : /* Assume the exclusion operators are strict */
4029 heikki.linnakangas@i 998 [ - + ]: 172 : if (existing_isnull[i])
4029 heikki.linnakangas@i 999 :UBC 0 : return false;
1000 : :
4029 heikki.linnakangas@i 1001 [ + + ]:CBC 172 : if (!DatumGetBool(OidFunctionCall2Coll(constr_procs[i],
1002 : 172 : index->rd_indcollation[i],
1003 : 172 : existing_values[i],
1004 : 172 : new_values[i])))
1005 : 36 : return false;
1006 : : }
1007 : :
1008 : 56 : return true;
1009 : : }
1010 : :
1011 : : /*
1012 : : * Check if ExecInsertIndexTuples() should pass indexUnchanged hint.
1013 : : *
1014 : : * When the executor performs an UPDATE that requires a new round of index
1015 : : * tuples, determine if we should pass 'indexUnchanged' = true hint for one
1016 : : * single index.
1017 : : */
1018 : : static bool
1938 pg@bowt.ie 1019 : 284156 : index_unchanged_by_update(ResultRelInfo *resultRelInfo, EState *estate,
1020 : : IndexInfo *indexInfo, Relation indexRelation)
1021 : : {
1022 : : Bitmapset *updatedCols;
1023 : : Bitmapset *extraUpdatedCols;
1024 : : Bitmapset *allUpdatedCols;
1025 : 284156 : bool hasexpression = false;
1026 : : List *idxExprs;
1027 : :
1028 : : /*
1029 : : * Check cache first
1030 : : */
1574 1031 [ + + ]: 284156 : if (indexInfo->ii_CheckedUnchanged)
1032 : 261575 : return indexInfo->ii_IndexUnchanged;
1033 : 22581 : indexInfo->ii_CheckedUnchanged = true;
1034 : :
1035 : : /*
1036 : : * Check for indexed attribute overlap with updated columns.
1037 : : *
1038 : : * Only do this for key columns. A change to a non-key column within an
1039 : : * INCLUDE index should not be counted here. Non-key column values are
1040 : : * opaque payload state to the index AM, a little like an extra table TID.
1041 : : *
1042 : : * Note that row-level BEFORE triggers won't affect our behavior, since
1043 : : * they don't affect the updatedCols bitmaps generally. It doesn't seem
1044 : : * worth the trouble of checking which attributes were changed directly.
1045 : : */
1046 : 22581 : updatedCols = ExecGetUpdatedCols(resultRelInfo, estate);
1047 : 22581 : extraUpdatedCols = ExecGetExtraUpdatedCols(resultRelInfo, estate);
1938 1048 [ + + ]: 25043 : for (int attr = 0; attr < indexInfo->ii_NumIndexKeyAttrs; attr++)
1049 : : {
1050 : 23687 : int keycol = indexInfo->ii_IndexAttrNumbers[attr];
1051 : :
1052 [ + + ]: 23687 : if (keycol <= 0)
1053 : : {
1054 : : /*
1055 : : * Skip expressions for now, but remember to deal with them later
1056 : : * on
1057 : : */
1058 : 19 : hasexpression = true;
1059 : 19 : continue;
1060 : : }
1061 : :
1062 [ + + ]: 23668 : if (bms_is_member(keycol - FirstLowInvalidHeapAttributeNumber,
1063 [ - + ]: 2443 : updatedCols) ||
1064 : 2443 : bms_is_member(keycol - FirstLowInvalidHeapAttributeNumber,
1065 : : extraUpdatedCols))
1066 : : {
1067 : : /* Changed key column -- don't hint for this index */
1574 1068 : 21225 : indexInfo->ii_IndexUnchanged = false;
1938 1069 : 21225 : return false;
1070 : : }
1071 : : }
1072 : :
1073 : : /*
1074 : : * When we get this far and index has no expressions, return true so that
1075 : : * index_insert() call will go on to pass 'indexUnchanged' = true hint.
1076 : : *
1077 : : * The _absence_ of an indexed key attribute that overlaps with updated
1078 : : * attributes (in addition to the total absence of indexed expressions)
1079 : : * shows that the index as a whole is logically unchanged by UPDATE.
1080 : : */
1081 [ + + ]: 1356 : if (!hasexpression)
1082 : : {
1574 1083 : 1341 : indexInfo->ii_IndexUnchanged = true;
1938 1084 : 1341 : return true;
1085 : : }
1086 : :
1087 : : /*
1088 : : * Need to pass only one bms to expression_tree_walker helper function.
1089 : : * Avoid allocating memory in common case where there are no extra cols.
1090 : : */
1091 [ + - ]: 15 : if (!extraUpdatedCols)
1092 : 15 : allUpdatedCols = updatedCols;
1093 : : else
1938 pg@bowt.ie 1094 :UBC 0 : allUpdatedCols = bms_union(updatedCols, extraUpdatedCols);
1095 : :
1096 : : /*
1097 : : * We have to work slightly harder in the event of indexed expressions,
1098 : : * but the principle is the same as before: try to find columns (Vars,
1099 : : * actually) that overlap with known-updated columns.
1100 : : *
1101 : : * If we find any matching Vars, don't pass hint for index. Otherwise
1102 : : * pass hint.
1103 : : */
1938 pg@bowt.ie 1104 :CBC 15 : idxExprs = RelationGetIndexExpressions(indexRelation);
1105 : 15 : hasexpression = index_expression_changed_walker((Node *) idxExprs,
1106 : : allUpdatedCols);
1107 : 15 : list_free(idxExprs);
1108 [ - + ]: 15 : if (extraUpdatedCols)
1938 pg@bowt.ie 1109 :UBC 0 : bms_free(allUpdatedCols);
1110 : :
1938 pg@bowt.ie 1111 [ + + ]:CBC 15 : if (hasexpression)
1112 : : {
1574 1113 : 11 : indexInfo->ii_IndexUnchanged = false;
1938 1114 : 11 : return false;
1115 : : }
1116 : :
1117 : : /*
1118 : : * Deliberately don't consider index predicates. We should even give the
1119 : : * hint when result rel's "updated tuple" has no corresponding index
1120 : : * tuple, which is possible with a partial index (provided the usual
1121 : : * conditions are met).
1122 : : */
1574 1123 : 4 : indexInfo->ii_IndexUnchanged = true;
1938 1124 : 4 : return true;
1125 : : }
1126 : :
1127 : : /*
1128 : : * Indexed expression helper for index_unchanged_by_update().
1129 : : *
1130 : : * Returns true when Var that appears within allUpdatedCols located.
1131 : : */
1132 : : static bool
1133 : 47 : index_expression_changed_walker(Node *node, Bitmapset *allUpdatedCols)
1134 : : {
1135 [ - + ]: 47 : if (node == NULL)
1938 pg@bowt.ie 1136 :UBC 0 : return false;
1137 : :
1938 pg@bowt.ie 1138 [ + + ]:CBC 47 : if (IsA(node, Var))
1139 : : {
1140 : 15 : Var *var = (Var *) node;
1141 : :
1142 [ + + ]: 15 : if (bms_is_member(var->varattno - FirstLowInvalidHeapAttributeNumber,
1143 : : allUpdatedCols))
1144 : : {
1145 : : /* Var was updated -- indicates that we should not hint */
1146 : 11 : return true;
1147 : : }
1148 : :
1149 : : /* Still haven't found a reason to not pass the hint */
1150 : 4 : return false;
1151 : : }
1152 : :
1153 : 32 : return expression_tree_walker(node, index_expression_changed_walker,
1154 : : allUpdatedCols);
1155 : : }
1156 : :
1157 : : /*
1158 : : * ExecWithoutOverlapsNotEmpty - raise an error if the tuple has an empty
1159 : : * range or multirange in the given attribute.
1160 : : */
1161 : : static void
595 peter@eisentraut.org 1162 : 3009 : ExecWithoutOverlapsNotEmpty(Relation rel, NameData attname, Datum attval, char typtype, Oid atttypid)
1163 : : {
1164 : : bool isempty;
1165 : : RangeType *r;
1166 : : MultirangeType *mr;
1167 : :
1168 [ + + - ]: 3009 : switch (typtype)
1169 : : {
1170 : 2321 : case TYPTYPE_RANGE:
1171 : 2321 : r = DatumGetRangeTypeP(attval);
1172 : 2321 : isempty = RangeIsEmpty(r);
1173 : 2321 : break;
1174 : 688 : case TYPTYPE_MULTIRANGE:
1175 : 688 : mr = DatumGetMultirangeTypeP(attval);
1176 : 688 : isempty = MultirangeIsEmpty(mr);
1177 : 688 : break;
595 peter@eisentraut.org 1178 :UBC 0 : default:
1179 [ # # ]: 0 : elog(ERROR, "WITHOUT OVERLAPS column \"%s\" is not a range or multirange",
1180 : : NameStr(attname));
1181 : : }
1182 : :
1183 : : /* Report a CHECK_VIOLATION */
595 peter@eisentraut.org 1184 [ + + ]:CBC 3009 : if (isempty)
1185 [ + - ]: 56 : ereport(ERROR,
1186 : : (errcode(ERRCODE_CHECK_VIOLATION),
1187 : : errmsg("empty WITHOUT OVERLAPS value found in column \"%s\" in relation \"%s\"",
1188 : : NameStr(attname), RelationGetRelationName(rel))));
1189 : 2953 : }
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