From: Tom Lane Date: Wed, 15 Aug 2007 19:16:12 +0000 (+0000) Subject: Repair problems occurring when multiple RI updates have to be done to the same X-Git-Tag: REL8_0_14~19 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5a3ec023120e504e6ba1f9b68069d8949e4222d4;p=thirdparty%2Fpostgresql.git Repair problems occurring when multiple RI updates have to be done to the same row within one query: we were firing check triggers before all the updates were done, leading to bogus failures. Fix by making the triggers queued by an RI update go at the end of the outer query's trigger event list, thereby effectively making the processing "breadth-first". This was indeed how it worked pre-8.0, so the bug does not occur in the 7.x branches. Per report from Pavel Stehule. --- diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c index a6b75f06d58..14f8980a99e 100644 --- a/src/backend/commands/trigger.c +++ b/src/backend/commands/trigger.c @@ -7,7 +7,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.177.4.3 2006/01/12 21:49:16 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.177.4.4 2007/08/15 19:16:12 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -2340,10 +2340,12 @@ AfterTriggerEndQuery(void) * SET CONSTRAINTS ... IMMEDIATE: all events we have decided to defer * will be available for it to fire. * + * We loop in case a trigger queues more events. + * * If we find no firable events, we don't have to increment firing_counter. */ events = &afterTriggers->query_stack[afterTriggers->query_depth]; - if (afterTriggerMarkEvents(events, &afterTriggers->events, true)) + while (afterTriggerMarkEvents(events, &afterTriggers->events, true)) { CommandId firing_id = afterTriggers->firing_counter++; @@ -2834,7 +2836,7 @@ AfterTriggerSetState(ConstraintsSetStmt *stmt) { AfterTriggerEventList *events = &afterTriggers->events; - if (afterTriggerMarkEvents(events, NULL, true)) + while (afterTriggerMarkEvents(events, NULL, true)) { CommandId firing_id = afterTriggers->firing_counter++; diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c index 71e40ed25b4..77e2cafb109 100644 --- a/src/backend/executor/spi.c +++ b/src/backend/executor/spi.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/executor/spi.c,v 1.133.4.2 2007/03/17 03:16:03 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/executor/spi.c,v 1.133.4.3 2007/08/15 19:16:12 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -39,9 +39,9 @@ static void _SPI_prepare_plan(const char *src, _SPI_plan *plan); static int _SPI_execute_plan(_SPI_plan *plan, Datum *Values, const char *Nulls, Snapshot snapshot, Snapshot crosscheck_snapshot, - bool read_only, int tcount); + bool read_only, bool fire_triggers, int tcount); -static int _SPI_pquery(QueryDesc *queryDesc, int tcount); +static int _SPI_pquery(QueryDesc *queryDesc, bool fire_triggers, int tcount); static void _SPI_error_callback(void *arg); @@ -301,7 +301,7 @@ SPI_execute(const char *src, bool read_only, int tcount) res = _SPI_execute_plan(&plan, NULL, NULL, InvalidSnapshot, InvalidSnapshot, - read_only, tcount); + read_only, true, tcount); _SPI_end_call(true); return res; @@ -334,7 +334,7 @@ SPI_execute_plan(void *plan, Datum *Values, const char *Nulls, res = _SPI_execute_plan((_SPI_plan *) plan, Values, Nulls, InvalidSnapshot, InvalidSnapshot, - read_only, tcount); + read_only, true, tcount); _SPI_end_call(true); return res; @@ -349,9 +349,12 @@ SPI_execp(void *plan, Datum *Values, const char *Nulls, int tcount) /* * SPI_execute_snapshot -- identical to SPI_execute_plan, except that we allow - * the caller to specify exactly which snapshots to use. This is currently - * not documented in spi.sgml because it is only intended for use by RI - * triggers. + * the caller to specify exactly which snapshots to use. Also, the caller + * may specify that AFTER triggers should be queued as part of the outer + * query rather than being fired immediately at the end of the command. + * + * This is currently not documented in spi.sgml because it is only intended + * for use by RI triggers. * * Passing snapshot == InvalidSnapshot will select the normal behavior of * fetching a new snapshot for each query. @@ -360,7 +363,7 @@ int SPI_execute_snapshot(void *plan, Datum *Values, const char *Nulls, Snapshot snapshot, Snapshot crosscheck_snapshot, - bool read_only, int tcount) + bool read_only, bool fire_triggers, int tcount) { int res; @@ -377,7 +380,7 @@ SPI_execute_snapshot(void *plan, res = _SPI_execute_plan((_SPI_plan *) plan, Values, Nulls, snapshot, crosscheck_snapshot, - read_only, tcount); + read_only, fire_triggers, tcount); _SPI_end_call(true); return res; @@ -1317,12 +1320,14 @@ _SPI_prepare_plan(const char *src, _SPI_plan *plan) * behavior of taking a new snapshot for each query. * crosscheck_snapshot: for RI use, all others pass InvalidSnapshot * read_only: TRUE for read-only execution (no CommandCounterIncrement) + * fire_triggers: TRUE to fire AFTER triggers at end of query (normal case); + * FALSE means any AFTER triggers are postponed to end of outer query * tcount: execution tuple-count limit, or 0 for none */ static int _SPI_execute_plan(_SPI_plan *plan, Datum *Values, const char *Nulls, Snapshot snapshot, Snapshot crosscheck_snapshot, - bool read_only, int tcount) + bool read_only, bool fire_triggers, int tcount) { volatile int res = 0; Snapshot saveActiveSnapshot; @@ -1473,7 +1478,7 @@ _SPI_execute_plan(_SPI_plan *plan, Datum *Values, const char *Nulls, crosscheck_snapshot, dest, paramLI, false); - res = _SPI_pquery(qdesc, + res = _SPI_pquery(qdesc, fire_triggers, queryTree->canSetTag ? tcount : 0); FreeQueryDesc(qdesc); } @@ -1506,7 +1511,7 @@ fail: } static int -_SPI_pquery(QueryDesc *queryDesc, int tcount) +_SPI_pquery(QueryDesc *queryDesc, bool fire_triggers, int tcount) { int operation = queryDesc->operation; int res; @@ -1540,7 +1545,8 @@ _SPI_pquery(QueryDesc *queryDesc, int tcount) ResetUsage(); #endif - AfterTriggerBeginQuery(); + if (fire_triggers) + AfterTriggerBeginQuery(); ExecutorStart(queryDesc, false); @@ -1558,7 +1564,8 @@ _SPI_pquery(QueryDesc *queryDesc, int tcount) ExecutorEnd(queryDesc); /* Take care of any queued AFTER triggers */ - AfterTriggerEndQuery(); + if (fire_triggers) + AfterTriggerEndQuery(); if (queryDesc->dest->mydest == SPI) { diff --git a/src/backend/utils/adt/ri_triggers.c b/src/backend/utils/adt/ri_triggers.c index 46653423c1c..2577cdcd9b6 100644 --- a/src/backend/utils/adt/ri_triggers.c +++ b/src/backend/utils/adt/ri_triggers.c @@ -17,7 +17,7 @@ * * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group * - * $PostgreSQL: pgsql/src/backend/utils/adt/ri_triggers.c,v 1.76.4.1 2007/07/17 17:45:56 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/utils/adt/ri_triggers.c,v 1.76.4.2 2007/08/15 19:16:12 tgl Exp $ * * ---------- */ @@ -2709,7 +2709,7 @@ RI_Initial_Check(FkConstraint *fkconstraint, Relation rel, Relation pkrel) NULL, NULL, CopySnapshot(GetLatestSnapshot()), InvalidSnapshot, - true, 1); + true, false, 1); /* Check result */ if (spi_result != SPI_OK_SELECT) @@ -3139,7 +3139,7 @@ ri_PerformCheck(RI_QueryKey *qkey, void *qplan, spi_result = SPI_execute_snapshot(qplan, vals, nulls, test_snapshot, crosscheck_snapshot, - false, limit); + false, false, limit); /* Restore UID */ SetUserId(save_uid); diff --git a/src/include/executor/spi.h b/src/include/executor/spi.h index d5ba89fa3ea..8ec13ca45b8 100644 --- a/src/include/executor/spi.h +++ b/src/include/executor/spi.h @@ -2,7 +2,7 @@ * * spi.h * - * $PostgreSQL: pgsql/src/include/executor/spi.h,v 1.50 2004/11/16 18:10:13 tgl Exp $ + * $PostgreSQL: pgsql/src/include/executor/spi.h,v 1.50.4.1 2007/08/15 19:16:12 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -92,7 +92,7 @@ extern int SPI_execute_snapshot(void *plan, Datum *Values, const char *Nulls, Snapshot snapshot, Snapshot crosscheck_snapshot, - bool read_only, int tcount); + bool read_only, bool fire_triggers, int tcount); extern void *SPI_prepare(const char *src, int nargs, Oid *argtypes); extern void *SPI_saveplan(void *plan); extern int SPI_freeplan(void *plan); diff --git a/src/test/regress/expected/foreign_key.out b/src/test/regress/expected/foreign_key.out index a479f4932a8..72e41a48947 100644 --- a/src/test/regress/expected/foreign_key.out +++ b/src/test/regress/expected/foreign_key.out @@ -646,7 +646,6 @@ SELECT * from FKTABLE; UPDATE PKTABLE set ptest2=5 where ptest2=2; ERROR: insert or update on table "fktable" violates foreign key constraint "constrname3" DETAIL: Key (ftest1,ftest2,ftest3)=(1,-1,3) is not present in table "pktable". -CONTEXT: SQL statement "UPDATE ONLY "public"."fktable" SET "ftest2" = DEFAULT WHERE "ftest1" = $1 AND "ftest2" = $2 AND "ftest3" = $3" -- Try to update something that will set default UPDATE PKTABLE set ptest1=0, ptest2=5, ptest3=10 where ptest2=2; UPDATE PKTABLE set ptest2=10 where ptest2=4; @@ -1207,3 +1206,71 @@ ROLLBACK TO savept1; COMMIT; ERROR: insert or update on table "fktable" violates foreign key constraint "fktable_fk_fkey" DETAIL: Key (fk)=(20) is not present in table "pktable". +-- test order of firing of FK triggers when several RI-induced changes need to +-- be made to the same row. This was broken by subtransaction-related +-- changes in 8.0. +CREATE TEMP TABLE users ( + id INT PRIMARY KEY, + name VARCHAR NOT NULL +); +NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "users_pkey" for table "users" +INSERT INTO users VALUES (1, 'Jozko'); +INSERT INTO users VALUES (2, 'Ferko'); +INSERT INTO users VALUES (3, 'Samko'); +CREATE TEMP TABLE tasks ( + id INT PRIMARY KEY, + owner INT REFERENCES users ON UPDATE CASCADE ON DELETE SET NULL, + worker INT REFERENCES users ON UPDATE CASCADE ON DELETE SET NULL, + checked_by INT REFERENCES users ON UPDATE CASCADE ON DELETE SET NULL +); +NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "tasks_pkey" for table "tasks" +INSERT INTO tasks VALUES (1,1,NULL,NULL); +INSERT INTO tasks VALUES (2,2,2,NULL); +INSERT INTO tasks VALUES (3,3,3,3); +SELECT * FROM tasks; + id | owner | worker | checked_by +----+-------+--------+------------ + 1 | 1 | | + 2 | 2 | 2 | + 3 | 3 | 3 | 3 +(3 rows) + +UPDATE users SET id = 4 WHERE id = 3; +SELECT * FROM tasks; + id | owner | worker | checked_by +----+-------+--------+------------ + 1 | 1 | | + 2 | 2 | 2 | + 3 | 4 | 4 | 4 +(3 rows) + +DELETE FROM users WHERE id = 4; +SELECT * FROM tasks; + id | owner | worker | checked_by +----+-------+--------+------------ + 1 | 1 | | + 2 | 2 | 2 | + 3 | | | +(3 rows) + +-- could fail with only 2 changes to make, if row was already updated +BEGIN; +UPDATE tasks set id=id WHERE id=2; +SELECT * FROM tasks; + id | owner | worker | checked_by +----+-------+--------+------------ + 1 | 1 | | + 3 | | | + 2 | 2 | 2 | +(3 rows) + +DELETE FROM users WHERE id = 2; +SELECT * FROM tasks; + id | owner | worker | checked_by +----+-------+--------+------------ + 1 | 1 | | + 3 | | | + 2 | | | +(3 rows) + +COMMIT; diff --git a/src/test/regress/sql/foreign_key.sql b/src/test/regress/sql/foreign_key.sql index dee046a1952..562796ecceb 100644 --- a/src/test/regress/sql/foreign_key.sql +++ b/src/test/regress/sql/foreign_key.sql @@ -855,3 +855,45 @@ ROLLBACK TO savept1; -- should catch error from initial INSERT COMMIT; + +-- test order of firing of FK triggers when several RI-induced changes need to +-- be made to the same row. This was broken by subtransaction-related +-- changes in 8.0. + +CREATE TEMP TABLE users ( + id INT PRIMARY KEY, + name VARCHAR NOT NULL +); + +INSERT INTO users VALUES (1, 'Jozko'); +INSERT INTO users VALUES (2, 'Ferko'); +INSERT INTO users VALUES (3, 'Samko'); + +CREATE TEMP TABLE tasks ( + id INT PRIMARY KEY, + owner INT REFERENCES users ON UPDATE CASCADE ON DELETE SET NULL, + worker INT REFERENCES users ON UPDATE CASCADE ON DELETE SET NULL, + checked_by INT REFERENCES users ON UPDATE CASCADE ON DELETE SET NULL +); + +INSERT INTO tasks VALUES (1,1,NULL,NULL); +INSERT INTO tasks VALUES (2,2,2,NULL); +INSERT INTO tasks VALUES (3,3,3,3); + +SELECT * FROM tasks; + +UPDATE users SET id = 4 WHERE id = 3; + +SELECT * FROM tasks; + +DELETE FROM users WHERE id = 4; + +SELECT * FROM tasks; + +-- could fail with only 2 changes to make, if row was already updated +BEGIN; +UPDATE tasks set id=id WHERE id=2; +SELECT * FROM tasks; +DELETE FROM users WHERE id = 2; +SELECT * FROM tasks; +COMMIT;