数据库原理及应用-期末考试试题及答案(2)(4)

FROM S

WHERE CITY='天津'));

评分标准：

SELECT JNO

FROM J

WHERE JNO NOT IN 和

SELECT JNO FROM SPJ

WHERE SNO IN

和

SELECT SNO FROM S

WHERE CITY='天津'

三层嵌套各1分，各嵌套内有错误则该项均不给分。

参考答案2：

SELECT JNO FROM J

WHERE NOT EXISTS (SELECT * FROM SPJ,S

WHERE SPJ.SNO=S.SNO AND

SPJ.JNO=J.JNO AND CITY='天津');

评分标准：

SELECT JNO FROM J

WHERE NOT EXISTS 1分； SELECT *

FROM SPJ,S 1分，SPJ,S少一个表不给分； WHERE SPJ.SNO=S.SNO AND

SPJ.JNO=J.JNO AND

CITY='天津'1分，三个条件少一个扣0.5，扣完1分为止。

参考答案3：

SELECT JNO

FROM J

WHERE NOT EXISTS