列级触发器 例子

create or replace trigger TRIG_Resources_Update
after update of state
ON Resources
REFERENCING OLD AS OLD NEW AS NEW
FOR EACH ROW
begin
       if(:OLD.state=1 and :NEW.state=2 and :OLD.catalogid=18235) then
                delete from policy where policy.id = :NEW.sourceid; 
       end if;
end;