On Tue, Dec 17, 2013 at 3:27 AM, Marko Tiikkaja <ma...@joh.to> wrote: > On 12/17/13, 4:53 AM, Robert Haas wrote: >>> >>> Well, I'm specifically thinking of master partition tables. In that >>> case, we really want an INSTEAD OF trigger. >> >> /me scratches head. >> >> So, put a BEFORE trigger, and make it return NULL. Same effect, >> different notation. > > > But it's not the same effect at all, that's the point: > > =# create view foov as select 1 as a; > CREATE VIEW > > =# create function insteadof() returns trigger as $$ > $# begin > $# -- INSERT here > $# return new; > $# end > $# $$ language plpgsql; > CREATE FUNCTION > > =# create function before() returns trigger as $$ > $# begin > $# -- INSERT here > $# return null; > $# end > $# $$ language plpgsql; > CREATE FUNCTION > > =# create trigger t1 instead of insert on foov for each row execute > procedure insteadof(); > CREATE TRIGGER > > =# create trigger t2 before insert on bart for each row execute procedure > before(); > CREATE TRIGGER > > =# insert into foov values (1) returning *; > a > --- > 1 > (1 row) > > INSERT 0 1 > > local:marko=#* insert into bart values (1) returning *; > a > --- > (0 rows) > > INSERT 0 0
Ah, interesting point. I didn't realize it worked like that. That does seem like a mighty useful thing to be able to do. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
