题目：查询选修了全部课程的学生学号和姓名。
喵查答案：select sno,sname from student where sno in( select sno from sc group by sno having count(cno)=(select count(*) from course)) ; SELECT SNO,SNAME FROM STUDENT S WHERE NOT EXISTS(SELECT * FROM COURSE C WHERE NOT EXISTS( SELECT * FROM SC WHERE S.SNO=SC.SNO AND C.CNO=SC.CNO ) )
