问题详情

检索选修四门以上课程的学生总成绩(不统计不及格的课程)，并要求按总成绩的降序排列出来。正确的SELECT语句是______。
A．SELECT S#, SUM(GRADE) FROM SC WHERE GRADE＞=60 GROUP BY S# ORDER BY 2 DESC HAVING COUNT(*)＞=4
B．SELECT S#, SUM(GRADE) FROM SC WHERE GRADE＞=60 GROUP BY S# HAVING COUNT(*)＞=4 ORDER BY 2 DESC
C．SELECT S#, SUM(GRADE) FROM SC WHERE GRADE＞=60 HAVING COUNT(*)＞=4 GROUP BY S# ORDER BY 2 DESC
D．SELECT S#, SUM(GRADE)FROM SC WHERE GRADE＞=60 ORDER BY 2 DESC GROUP BY S# HAVING COUNT(*)＞=4请帮忙给出正确答案和分析，谢谢！