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主键(主关系键、主关键字、主码)

名词解释题
2022-01-01 17:38
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正确答案

主键是从多个候选键中选出的一个关系键,用来唯一标识实体的个体,在关系中用来作为插入、删除、检索元组的操作变量。


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