diff options
Diffstat (limited to 'src/backend/utils/adt/ri_triggers.c')
| -rw-r--r-- | src/backend/utils/adt/ri_triggers.c | 20 |
1 files changed, 9 insertions, 11 deletions
diff --git a/src/backend/utils/adt/ri_triggers.c b/src/backend/utils/adt/ri_triggers.c index 0c1d67e4934..a5db63e0f6d 100644 --- a/src/backend/utils/adt/ri_triggers.c +++ b/src/backend/utils/adt/ri_triggers.c @@ -42,6 +42,7 @@ #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" @@ -289,20 +290,17 @@ RI_FKey_check(PG_FUNCTION_ARGS) * We should not even consider checking the row if it is no longer valid, * since it was either deleted (so the deferred check should be skipped) * or updated (in which case only the latest version of the row should be - * checked).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. |