• 2022-06-19
    Employees表中lastname列保存顾客的姓,firstname列保存顾客的名。现在需要查询顾客姓名的组合,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 employees
    B: select * from employees order by lastname,firstname
    C: select lastname+firstname from employees
    D: select lastname and firstname from employees
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