[单选题]

查询选修了课程号为“C1”的学生的姓名和年龄,若用下列SQL的SELECT语句表达 时,错误的是( )。

A.SELECT SNAME,AGE FROM S WHERE S .S#=(SELECT S

C.S# FROM SC WHERE

C.C#=’C 1’)

B.SELECT SNAME,AGE FROM S,SC WHERE S.S#=S

C.S# AND S

C.C#=’C 1’

C.SELECT SNAME,AGE FROM S,SC WHERE S.S#=S

C.S# AND S

C.C#=’CI’ ORDER B Y S.S#

D.SELECT SNAME,AGE FROM S WHERE S.S#=(SELECT S

C.S# FROM SC WHERE S

C.C#=’C 1’)

参考答案与解析: