From 7fc0f06221d22632daa3ff8b70919b43e8a242ca Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 20 Nov 2009 20:38:12 +0000 Subject: 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. --- src/backend/commands/tablecmds.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) (limited to 'src/backend/commands/tablecmds.c') diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 3e0c8191c7e..1de19504531 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.305 2009/11/04 12:24:23 heikki Exp $ + * $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.306 2009/11/20 20:38:10 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -5403,7 +5403,7 @@ validateForeignKeyConstraint(Constraint *fkconstraint, trig.tgconstraint = constraintOid; trig.tgdeferrable = FALSE; trig.tginitdeferred = FALSE; - /* we needn't fill in tgargs */ + /* we needn't fill in tgargs or tgqual */ /* * See if we can do it with a single LEFT JOIN query. A FALSE result @@ -5476,13 +5476,14 @@ CreateFKCheckTrigger(RangeVar *myRel, Constraint *fkconstraint, } fk_trigger->columns = NIL; + fk_trigger->whenClause = NULL; fk_trigger->isconstraint = true; fk_trigger->deferrable = fkconstraint->deferrable; fk_trigger->initdeferred = fkconstraint->initdeferred; fk_trigger->constrrel = fkconstraint->pktable; fk_trigger->args = NIL; - (void) CreateTrigger(fk_trigger, constraintOid, indexOid, + (void) CreateTrigger(fk_trigger, NULL, constraintOid, indexOid, "RI_ConstraintTrigger", false); /* Make changes-so-far visible */ @@ -5527,6 +5528,7 @@ createForeignKeyTriggers(Relation rel, Constraint *fkconstraint, fk_trigger->row = true; fk_trigger->events = TRIGGER_TYPE_DELETE; fk_trigger->columns = NIL; + fk_trigger->whenClause = NULL; fk_trigger->isconstraint = true; fk_trigger->constrrel = myRel; switch (fkconstraint->fk_del_action) @@ -5563,7 +5565,7 @@ createForeignKeyTriggers(Relation rel, Constraint *fkconstraint, } fk_trigger->args = NIL; - (void) CreateTrigger(fk_trigger, constraintOid, indexOid, + (void) CreateTrigger(fk_trigger, NULL, constraintOid, indexOid, "RI_ConstraintTrigger", false); /* Make changes-so-far visible */ @@ -5580,6 +5582,7 @@ createForeignKeyTriggers(Relation rel, Constraint *fkconstraint, fk_trigger->row = true; fk_trigger->events = TRIGGER_TYPE_UPDATE; fk_trigger->columns = NIL; + fk_trigger->whenClause = NULL; fk_trigger->isconstraint = true; fk_trigger->constrrel = myRel; switch (fkconstraint->fk_upd_action) @@ -5616,7 +5619,7 @@ createForeignKeyTriggers(Relation rel, Constraint *fkconstraint, } fk_trigger->args = NIL; - (void) CreateTrigger(fk_trigger, constraintOid, indexOid, + (void) CreateTrigger(fk_trigger, NULL, constraintOid, indexOid, "RI_ConstraintTrigger", false); } -- cgit v1.2.3