【简答题】用SQL语句检索选修课程在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 0RDER BY平均成绩DESC B)SELECT学号,姓名,AVG(成绩)FROM S,SC; WHERE S.学号...
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
C.
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