diff options
Diffstat (limited to 'src/backend/commands/trigger.c')
| -rw-r--r-- | src/backend/commands/trigger.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c index 7a08ffca5e9..d5d90d57044 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 1.241 2008/11/21 20:14:27 mha Exp $ + * $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.242 2008/12/13 02:00:18 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -3716,12 +3716,28 @@ AfterTriggerSetState(ConstraintsSetStmt *stmt) if (!stmt->deferred) { AfterTriggerEventList *events = &afterTriggers->events; + bool snapshot_set = false; while (afterTriggerMarkEvents(events, NULL, true)) { CommandId firing_id = afterTriggers->firing_counter++; /* + * Make sure a snapshot has been established in case trigger + * functions need one. Note that we avoid setting a snapshot if + * we don't find at least one trigger that has to be fired now. + * This is so that BEGIN; SET CONSTRAINTS ...; SET TRANSACTION + * ISOLATION LEVEL SERIALIZABLE; ... works properly. (If we are + * at the start of a transaction it's not possible for any trigger + * events to be queued yet.) + */ + if (!snapshot_set) + { + PushActiveSnapshot(GetTransactionSnapshot()); + snapshot_set = true; + } + + /* * We can delete fired events if we are at top transaction level, * but we'd better not if inside a subtransaction, since the * subtransaction could later get rolled back. @@ -3730,6 +3746,9 @@ AfterTriggerSetState(ConstraintsSetStmt *stmt) !IsSubTransaction())) break; /* all fired */ } + + if (snapshot_set) + PopActiveSnapshot(); } } |