Marc Boucher <pgml(at)gmx(dot)net> writes:
> CREATE OR REPLACE RULE albed_updalb3_rl AS
> ON UPDATE TO album WHERE new.pls_id != old.pls_id
> DO
> UPDATE album_edit SET pls_id=new.pls_id WHERE alb_id=new.id;
> It works until new.pls_id or old.pls_id is null. The rule is still called
> (based on my test), but the "DO" query is not executed correctly.
That's not a bug. "foo != NULL" does not yield true, it yields NULL.
You could test for nulls with IS NULL, or possibly use the IS DISTINCT
FROM construct (does 7.3 have that? I forget.)
regards, tom lane