SQL server查询出只选修两门课程的学生学号和姓名

代码段：

SELECT score.SId AS 学号,student.Sname AS 姓名
FROM score
LEFT JOIN student ON score.SId=student.SId
WHERE score.SId IN 
(SELECT score.SId
FROM score
GROUP BY score.SId
HAVING COUNT(score.CId)=2
)
GROUP BY score.SId,student.Sname

表：

score

student