问题
单项选择题
查询选修了课程号为,C2,的学生号和姓名,若用下列SQL的SELECT语句表达时,错误的是( )。
A.SELECT S.S#,SNAME FROM S WHERE S.S#
=(SELECT SC.S# FROM SC WHERE C#='C2')
B.SELECT S.S#,SNAME FROM S,SC
WHERE S.S#=SC.S# AND C#='C2'
C.SELECT S.S#,SNAME FROM S,SC
WHERE S.S#=SC.S# AND C#='C2' ORDER BY S.S#
D.SELECT S.S#,SNAME FROM S WHERE S.S
IN (SELECT SC.S# FROM SC WHERE C ='C2')
答案
参考答案:A