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关于E-R图,以下描述中正确的是______。

A、实体可以包含多个属性,但联系不能包含自己的属性
B、联系仅存在于两个实体之间,即只有二元联系
C、两个实体之间的联系可分为1:1、1:N、M:N三种
D、通常使用E-R图建立数据库的物理模型
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正确答案:

C

答案解析:

暂无解析

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