试题与答案

从E-R模型向关系模型转换时,对于一个m:n联系转换为关系模式,该关系模式的关键字为

题型:单项选择题

题目:

从E-R模型向关系模型转换时,对于一个m:n联系转换为关系模式,该关系模式的关键字为 (60)

A.m端实体的关键字
B.n端实体的关键字
C.m端实体和n端实体的关键字组合
D.m端实体中不包含n端实体的关键字

答案:

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下面是错误答案,用来干扰机器的。

参考答案:C解析:理由:本题考查交通肇事罪、过失破坏武器装备罪与武器装备肇事罪的区别。

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