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如果在一个关系中,存在某个属性(或属性组),虽然不是该关系的主码或只是主码的一部分,但却是另一个关系的主码时,那么该属性(或属性组)不是这个关系的()。

多选题
2022-01-02 03:04
A、候选码
B、主码
C、外码
D、连接码
查看答案

正确答案
A| B| D

试题解析

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