問題詳情

35.用SQL语言检索选修课程在5门以上(含5门)的学生的学号、姓名和平均成绩,并按平均成绩降序排序,正确的命令是
(A)SELECT S.学号,姓名,平均成绩 FROM S,SC;WHERE S.学号=SC.学号;GROUP BY S.学号 HAVING COUNT(*)>=5 ORDER BY 平均成绩 DESC
(B)SELECT 学号,姓名,AVG(成绩) FROM S,SC;WHERE S.学号=SC.学号AND COUNT(*)>=5;GROUP BY 学号 ORDER BY 3 DESC
(C)SELECT S.学号,姓名,AVG(成绩) 平均成绩 FROM S,SC;WHERE S.学号=SC.学号AND COUNT(*)>=5;GROUP BY S.学号 ORDER BY 平均成绩 DESC
(D)SELECT S.学号,姓名,AVG(成绩) 平均成绩 FROM S,SC;WHERE S.学号=SC.学号;GROUP BY S.学号 HAVING COUNT(*)>=5 ORDER BY 3 DESC

參考答案

答案:D
難度:適中0.5
統計:A(0),B(0),C(0),D(0),E(0)