某数据库中有表COURSE(CNO,CNAME,TNO)和表TEACHER(TNO,TNAME,DEPART),完成查询选修某课程的同学人数多于5人的教师姓名。
SELECT TNAME
FROM TEACHER WHERE
(4)
(SELECT X.TNO FROM COURSE X,COURSE Y
WHERE (5)
(6)
(7) )

【参考答案】

HAVING COUNT(X.CNO)＞5