1
0
mirror of https://github.com/postgres/postgres.git synced 2025-06-16 06:01:02 +03:00

Add a WHEN clause to CREATE TRIGGER, allowing a boolean expression to be

checked to determine whether the trigger should be fired.

For BEFORE triggers this is mostly a matter of spec compliance; but for AFTER
triggers it can provide a noticeable performance improvement, since queuing of
a deferred trigger event and re-fetching of the row(s) at end of statement can
be short-circuited if the trigger does not need to be fired.

Takahiro Itagaki, reviewed by KaiGai Kohei.
This commit is contained in:
Tom Lane
2009-11-20 20:38:12 +00:00
parent 201a45c4fa
commit 7fc0f06221
27 changed files with 783 additions and 100 deletions

View File

@ -26,7 +26,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.334 2009/10/26 02:26:29 tgl Exp $
* $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.335 2009/11/20 20:38:10 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -752,6 +752,7 @@ InitPlan(QueryDesc *queryDesc, int eflags)
*/
estate->es_tupleTable = NIL;
estate->es_trig_tuple_slot = NULL;
estate->es_trig_oldtup_slot = NULL;
/* mark EvalPlanQual not active */
estate->es_epqTuple = NULL;
@ -911,6 +912,8 @@ InitResultRelInfo(ResultRelInfo *resultRelInfo,
resultRelInfo->ri_TrigFunctions = (FmgrInfo *)
palloc0(n * sizeof(FmgrInfo));
resultRelInfo->ri_TrigWhenExprs = (List **)
palloc0(n * sizeof(List *));
if (doInstrument)
resultRelInfo->ri_TrigInstrument = InstrAlloc(n);
else
@ -919,6 +922,7 @@ InitResultRelInfo(ResultRelInfo *resultRelInfo,
else
{
resultRelInfo->ri_TrigFunctions = NULL;
resultRelInfo->ri_TrigWhenExprs = NULL;
resultRelInfo->ri_TrigInstrument = NULL;
}
resultRelInfo->ri_ConstraintExprs = NULL;