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定义外键实现的是哪一类完整性
更新时间: 2020-10-04 00:00:00  

定义外键实现的是参照完整性,参照完整性是指控制数据一致性,尤其是不同表之间关系的规则,某个关系的主键相应的属性在另一关系中出现,此时该主键就是另一关系的外键,外键用于与另一张表的关联,能确定另一张表记录的字段,用于保持数据的一致性,所以说定义外键实现了参照完整性。

关键词: 定义 实现 一类 完整性

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