create table s5 (
 no int,
 name varchar(100),
 complete timestamp
);

CREATE FUNCTION s5_func() RETURNS trigger
AS
$function$
BEGIN
 UPDATE s5 SET complete = NULL where no=new.no;
 RETURN NULL;
END;
$function$
LANGUAGE plpgsql;

CREATE TRIGGER s5 before UPDATE ON s5
FOR EACH ROW EXECUTE PROCEDURE s5_func();

insert into s5 values(1, 'dd', now());

이렇게 한후...다음 쿼리문을 실행하면
update s5 set name='22' where no=1;

다음과 같이..
QL statement "UPDATE s5 SET complete = NULL where no= $1 "
PL/pgSQL function "s5_func" line 2 at SQL statement
SQL statement "UPDATE s5 SET complete = NULL where no= $1 "
PL/pgSQL function "s5_func" line 2 at SQL statement
SQL statement "UPDATE s5 SET complete = NULL where no= $1 "
PL/pgSQL function "s5_func" line 2 at SQL statement
SQL statement "UPDATE s5 SET complete = NULL where no= $1 "
PL/pgSQL function "s5_func" line 2 at SQL statement
SQL statement "UPDATE s5 SET complete = NULL where no= $1 "
PL/pgSQL function "s5_func" line 2 at SQL statement
뜨는데,,,..잘 모르겠어요..아시는분 부탁좀 드릴께요..;;;