--題目：編寫一個數據庫觸發器，當任何時候某個部門的從dept表中刪除的時,該觸發器將從emp表中刪除該部門的所有雇員。
CREATE OR REPLACE TRIGGER TRI_G1
BEFORE DELETE ON DEPT
FOR EACH ROW
BEGIN
DELETE FROM emp where DEPORTNO=:OLD.DEPT_NO;
END;
select * from emp
select * froM DEPT
INSERT INTO DEPT(DEPT_NO,DEPT_NAME) VALUES(3,'C')
BEGIN
INSERT INTO EMP(EMPNO,ENAME,SALARY,COMM,DEPORTNO) VALUES(7986,'gangge',2001,35000,3);
INSERT INTO EMP(EMPNO,ENAME,SALARY,COMM,DEPORTNO) VALUES(7895,'WA',2100,25000,3);
END;
DELETE FROM DEPT WHERE DEPT_NO=3