• 2022-06-18
    若S中有30行记录,执行以下SQL语句SELECT * FROM S A, S BWHERE A.CITY =B.CITY则运行结果的最大可能记录数maxNum和最小可能记录数minNum分别是——
    A: maxNum=30, minNum=0
    B: maxNum=60, minNum=30
    C: maxNum=900, minNum=30
    D: maxNum=900, minNum=60