Hi for all , plese a question ,this function can be write in pl/pgsql ??????? thank for all 2005/4/24, Stephane Bortzmeyer <bortzmeyer@xxxxxx>: > To protect the database from programming errors (there is a team > working on the project and some beginners may produce bugs), I would > like to flag some attributes as immutable, meaning non modifiable in > an UPDATE. (Typical examples are ID or creation time.) > > Currently, I use triggers: > > CREATE OR REPLACE FUNCTION check_immutable() RETURNS TRIGGER > AS 'BEGIN > IF NEW.id != OLD.id OR NEW.created != OLD.created THEN > RAISE EXCEPTION ''Change not allowed in that table''; > END IF; > RETURN NEW; > END;' > LANGUAGE PLPGSQL; > > CREATE TRIGGER check_immutable > BEFORE UPDATE ON MyTable > FOR EACH ROW > EXECUTE PROCEDURE check_immutable(); > > It is quite painful, since I need a function (with the list of > immutable attributes) and a trigger per table. If I INHERITS from a > table, triggers on the parent table are not called if I update the > child table. > > Is there a better way? I do not find a constraint IMMUTABLE for > attributes. > > PostgreSQL 7.4, switching to 8.0 would be difficult. > > ---------------------------(end of broadcast)--------------------------- > TIP 1: subscribe and unsubscribe commands go to majordomo@xxxxxxxxxxxxxx > -- cordialmente, Ing. Mario Soto Cordones ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster
