• 2022-06-19
    employee表中lastname列保存顾客姓,firstname列保存顾客的名,现在,需要查询顾客的姓名的组合,例如,lastname列中的”张“,同一行firstname列中的”国华“,查询结果应该返回”张国华“,则正确的查询语句应该是( )
    A: select lastname,firstname from employee
    B: select * from employee order by lastname,firstname
    C: select lastname+firstname from employee
    D: select lastname and firstname from employee
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