• 2022-05-30
    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, 是错误的?
    A: SELECT S.S
    B: ,SNAME FROM SWHERE S.S
    C: = (SELECT SS
    D: FROM SC WHERE C
    E: =‘C2’)
    F: SELECT S.S
    G: ,SNAME FROM S,SCWHERE S.S
    H: = SS
    I: AND C
    J: =‘C2’
    K: SELECT S.S
    L: ,SNAME FROM S,SCWHERE S.S
    M: = SS
    N: AND C
    O: =‘C2' ORDER BY S.S
    P: SELECT S.S
    Q: ,SNAME FROM SWHERE S.S
    R: IN(SELECT SS
    S: FROM SC WHERE C
    T: =‘C2' )
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