Re: sub query constraint

Yudie Pg wrote:
> CREATE OR REPLACE FUNCTION validate_actions_insert() RETRUNS OPAQUE AS '
CREATE OR REPLACE FUNCTION validate_actions_insert() RETURNS OPAQUE AS $$
> DECLARE
> rs RECORD;
>
> BEGIN
> SELECT INTO rs * FROM user_data WHERE name = NEW.user and write_access = 't';
>
> IF NOT FOUND THEN
> RAISE EXCEPTION ''writing access forbidden for user '', NEW.user;
RAISE EXCEPTION 'writing access forbidden for user %', NEW.user;
> END IF;
>
> RETURN NEW;
> END;
> ' LANGUAGE plpgsql;
$$ LANGUAGE plpgsql;
>
> CREATE TRIGGER tg_actions BEFORE INSERT OR UPDATE ON actions
> FOR EACH ROW EXECUTE PROCEDURE validate_actions_insert();

Yugi,
I made a few minor modifications as shown above and the trigger
function works great. I think I'll also use triggers to keep a history
of record changes for auditing.

Thanks,

Dale