定义和emp表的ename具有相同数据类型的变量v_ename,正确的代码是A.v_ename ename %typeB.v_ename emp.ename %typeC.v_ename emp.ename typeD.v_ename emp.ename %rowtype

定义和emp表的ename具有相同数据类型的变量v_ename,正确的代码是

A.v_ename ename %type

B.v_ename emp.ename %type

C.v_ename emp.ename type

D.v_ename emp.ename %rowtype


参考答案和解析
v_ename emp.ename %type

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