diff --git a/src/backend/utils/adt/ri_triggers.c b/src/backend/utils/adt/ri_triggers.c index b4765005feb..983f7647d7d 100644 --- a/src/backend/utils/adt/ri_triggers.c +++ b/src/backend/utils/adt/ri_triggers.c @@ -44,6 +44,7 @@ #include "parser/parse_coerce.h" #include "parser/parse_relation.h" #include "miscadmin.h" +#include "storage/bufmgr.h" #include "utils/acl.h" #include "utils/builtins.h" #include "utils/fmgroids.h" @@ -286,20 +287,17 @@ RI_FKey_check(TriggerData *trigdata) * We should not even consider checking the row if it is no longer valid, * since it was either deleted (so the deferred check should be skipped) * or updated (in which case only the latest version of the row should be - * checked). Test its liveness according to SnapshotSelf. - * - * NOTE: The normal coding rule is that one must acquire the buffer - * content lock to call HeapTupleSatisfiesVisibility. We can skip that - * here because we know that AfterTriggerExecute just fetched the tuple - * successfully, so there cannot be a VACUUM compaction in progress on the - * page (either heap_fetch would have waited for the VACUUM, or the - * VACUUM's LockBufferForCleanup would be waiting for us to drop pin). And - * since this is a row inserted by our open transaction, no one else can - * be entitled to change its xmin/xmax. + * checked). Test its liveness according to SnapshotSelf. We need pin + * and lock on the buffer to call HeapTupleSatisfiesVisibility. Caller + * should be holding pin, but not lock. */ - Assert(new_row_buf != InvalidBuffer); + LockBuffer(new_row_buf, BUFFER_LOCK_SHARE); if (!HeapTupleSatisfiesVisibility(new_row, SnapshotSelf, new_row_buf)) + { + LockBuffer(new_row_buf, BUFFER_LOCK_UNLOCK); return PointerGetDatum(NULL); + } + LockBuffer(new_row_buf, BUFFER_LOCK_UNLOCK); /* * Get the relation descriptors of the FK and PK tables. diff --git a/src/test/regress/expected/foreign_key.out b/src/test/regress/expected/foreign_key.out index 044881af711..46a30b44289 100644 --- a/src/test/regress/expected/foreign_key.out +++ b/src/test/regress/expected/foreign_key.out @@ -1381,3 +1381,24 @@ explain (costs off) delete from t1 where a = 1; (10 rows) delete from t1 where a = 1; +-- +-- Test deferred FK check on a tuple deleted by a rolled-back subtransaction +-- +create table pktable2(f1 int primary key); +create table fktable2(f1 int references pktable2 deferrable initially deferred); +insert into pktable2 values(1); +begin; +insert into fktable2 values(1); +savepoint x; +delete from fktable2; +rollback to x; +commit; +begin; +insert into fktable2 values(2); +savepoint x; +delete from fktable2; +rollback to x; +commit; -- fail +ERROR: insert or update on table "fktable2" violates foreign key constraint "fktable2_f1_fkey" +DETAIL: Key (f1)=(2) is not present in table "pktable2". +drop table pktable2, fktable2; diff --git a/src/test/regress/sql/foreign_key.sql b/src/test/regress/sql/foreign_key.sql index 85c9d04d64f..cc36ab5bafc 100644 --- a/src/test/regress/sql/foreign_key.sql +++ b/src/test/regress/sql/foreign_key.sql @@ -1019,3 +1019,26 @@ create rule r1 as on delete to t1 do delete from t2 where t2.b = old.a; explain (costs off) delete from t1 where a = 1; delete from t1 where a = 1; + +-- +-- Test deferred FK check on a tuple deleted by a rolled-back subtransaction +-- +create table pktable2(f1 int primary key); +create table fktable2(f1 int references pktable2 deferrable initially deferred); +insert into pktable2 values(1); + +begin; +insert into fktable2 values(1); +savepoint x; +delete from fktable2; +rollback to x; +commit; + +begin; +insert into fktable2 values(2); +savepoint x; +delete from fktable2; +rollback to x; +commit; -- fail + +drop table pktable2, fktable2;