5.42.txt

delphi renyuanguanlixinxioxitong

CREATE OR REPLACE TRIGGER tr_check_sal
BEFORE UPDATE OF sal on employee
FOR EACH ROW
WHEN (new.sal<old.sal or new.sal>1.2*old.sal)
BEGIN
  raise_application_error(-20101,'工资只升不降，且幅度不超过20%');
END tr_check_sal;