Student(Sid,Sname,Sage,Ssex) 学生表Course(Cid,Cname,Tid) 课程表SC(Sid,Cid,score) 成绩表Teacher(Tid,Tname) 教师表练习内容:1.查询“某1”课程比& ...
Student(Sid,Sname,Sage,Ssex) 学生表
Course(Cid,Cname,Tid) 课程表标准答案(但是好像不好使)SELECT Student.S#,Student.Sname FROM Student,SC WHERE Student.S#=SC.S# AND SC.C#='001'and exists( SELECT * FROM SC as SC_2 WHERE SC_2.S#=SC.S# AND SC_2.C#='002'); 标准答案:SELECT sid,Sname FROM Student WHERE sid in (SELECT sid FROM SC ,Course ,Teacher WHERE SC.cid=Course.cid AND Teacher.tid=Course.tid AND Teacher.Tname='杨巍巍' GROUP BY sid having count(SC.cid)=(SELECT count(cid) FROM Course,Teacher WHERE Teacher.tid=Course.tid AND Tname='杨巍巍'))标准答案:SELECT sid,Sname FROM (SELECT Student.sid,Student.Sname,score ,32.查询每门课程的平均成绩,结果按平均成绩升序排列,平均成绩相同时,按课程号降序排列41.查询各个课程及相应的选修人数48.查询两门以上不及格课程的同学的学号及其平均成绩
原标题:[转载]sql语句练习50题
关键词:sql
*特别声明:以上内容来自于网络收集,著作权属原作者所有,如有侵权,请联系我们:
admin#shaoqun.com
(#换成@)。