摘要: course: teachar: student sc: 1、查询“c001”课程比“c002”课程成绩高的所有学生的学号; select a.sid from (select sid,score from sc where cid=001) as a, (select sid,score from 阅读全文
posted @ 2020-10-21 20:43 明月路 阅读(122) 评论(0) 推荐(1)