摘要: select sname from student where not exists (select * from course where not exists (select * from sc where sno =student.sno and cno=course.cno); 最内部的 s 阅读全文
posted @ 2014-06-12 23:27 一杯半盏 阅读(1676) 评论(0) 推荐(0) 编辑