题目内容

下面有关E-R模型向关系模型转换的叙述中,正确的是( )。

A. 一个实体类型转换为一个关系模式
B. 一个1:1联系可以转换为一个独立的关系模式,也可以与联系的任意一端实体所对应的关系模式合并
C. 一个1:n联系可以转换为一个独立的关系模式,也可以与联系的任意一端实体所对应的关系模式合并
D. 一个m:n联系转换为一个关系模式

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