> Hi,
>
> Can you put a foreign key constraint on an array column that says that
> each element of the array must match a primary key?
>
> If not, is this a TODO perhaps?
>
> Chris
>
Hello,
Using array values for foreign key is very special. I not sure, so all
people need it. More interesting is CHECK on array. But you can write
simply trigger.
CREATE OR REPLACE FUNCTION check_() RETURNS TRIGGER AS $$
DECLARE _v integer;
BEGIN FOR _i IN array_lower(NEW.array_value,1) .. array_upper(NEW.array_value,1) LOOP PERFORM 1 FROM
some_tabWHERE pk = NEW.array_value[_i]; IF NOT FOUND THEN RAISE EXCEPTION '..........'; END IF; END LOOP;
RETURNNEW;
END; $$ LANGUAGE plpgsql;
CREATE TRIGGER foo BEFORE INSERT OR UPDATE ON ... FOR EACH ROW EXECUTE PROCEDURE check_();
Regards
Pavel Stehule
