diff options
Diffstat (limited to 'src/backend/commands/trigger.c')
| -rw-r--r-- | src/backend/commands/trigger.c | 58 |
1 files changed, 52 insertions, 6 deletions
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c index 54db16c9090..b502941b08b 100644 --- a/src/backend/commands/trigger.c +++ b/src/backend/commands/trigger.c @@ -401,6 +401,23 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("TRUNCATE triggers with transition tables are not supported"))); + /* + * We currently don't allow multi-event triggers ("INSERT OR + * UPDATE") with transition tables, because it's not clear how to + * handle INSERT ... ON CONFLICT statements which can fire both + * INSERT and UPDATE triggers. We show the inserted tuples to + * INSERT triggers and the updated tuples to UPDATE triggers, but + * it's not yet clear what INSERT OR UPDATE trigger should see. + * This restriction could be lifted if we can decide on the right + * semantics in a later release. + */ + if (((TRIGGER_FOR_INSERT(tgtype) ? 1 : 0) + + (TRIGGER_FOR_UPDATE(tgtype) ? 1 : 0) + + (TRIGGER_FOR_DELETE(tgtype) ? 1 : 0)) != 1) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("Transition tables cannot be specified for triggers with more than one event"))); + if (tt->isNew) { if (!(TRIGGER_FOR_INSERT(tgtype) || @@ -2128,8 +2145,10 @@ MakeTransitionCaptureState(TriggerDesc *trigdesc) CurrentResourceOwner = CurTransactionResourceOwner; if (trigdesc->trig_delete_old_table || trigdesc->trig_update_old_table) state->tcs_old_tuplestore = tuplestore_begin_heap(false, false, work_mem); - if (trigdesc->trig_insert_new_table || trigdesc->trig_update_new_table) - state->tcs_new_tuplestore = tuplestore_begin_heap(false, false, work_mem); + if (trigdesc->trig_insert_new_table) + state->tcs_insert_tuplestore = tuplestore_begin_heap(false, false, work_mem); + if (trigdesc->trig_update_new_table) + state->tcs_update_tuplestore = tuplestore_begin_heap(false, false, work_mem); } PG_CATCH(); { @@ -2147,8 +2166,10 @@ MakeTransitionCaptureState(TriggerDesc *trigdesc) void DestroyTransitionCaptureState(TransitionCaptureState *tcs) { - if (tcs->tcs_new_tuplestore != NULL) - tuplestore_end(tcs->tcs_new_tuplestore); + if (tcs->tcs_insert_tuplestore != NULL) + tuplestore_end(tcs->tcs_insert_tuplestore); + if (tcs->tcs_update_tuplestore != NULL) + tuplestore_end(tcs->tcs_update_tuplestore); if (tcs->tcs_old_tuplestore != NULL) tuplestore_end(tcs->tcs_old_tuplestore); pfree(tcs); @@ -3993,7 +4014,29 @@ AfterTriggerExecute(AfterTriggerEvent event, if (LocTriggerData.tg_trigger->tgoldtable) LocTriggerData.tg_oldtable = transition_capture->tcs_old_tuplestore; if (LocTriggerData.tg_trigger->tgnewtable) - LocTriggerData.tg_newtable = transition_capture->tcs_new_tuplestore; + { + /* + * Currently a trigger with transition tables may only be defined + * for a single event type (here AFTER INSERT or AFTER UPDATE, but + * not AFTER INSERT OR ...). + */ + Assert((TRIGGER_FOR_INSERT(LocTriggerData.tg_trigger->tgtype) != 0) ^ + (TRIGGER_FOR_UPDATE(LocTriggerData.tg_trigger->tgtype) != 0)); + + /* + * Show either the insert or update new tuple images, depending on + * which event type the trigger was registered for. A single + * statement may have produced both in the case of INSERT ... ON + * CONFLICT ... DO UPDATE, and in that case the event determines + * which tuplestore the trigger sees as the NEW TABLE. + */ + if (TRIGGER_FOR_INSERT(LocTriggerData.tg_trigger->tgtype)) + LocTriggerData.tg_newtable = + transition_capture->tcs_insert_tuplestore; + else + LocTriggerData.tg_newtable = + transition_capture->tcs_update_tuplestore; + } } /* @@ -5241,7 +5284,10 @@ AfterTriggerSaveEvent(EState *estate, ResultRelInfo *relinfo, Tuplestorestate *new_tuplestore; Assert(newtup != NULL); - new_tuplestore = transition_capture->tcs_new_tuplestore; + if (event == TRIGGER_EVENT_INSERT) + new_tuplestore = transition_capture->tcs_insert_tuplestore; + else + new_tuplestore = transition_capture->tcs_update_tuplestore; if (original_insert_tuple != NULL) tuplestore_puttuple(new_tuplestore, original_insert_tuple); |