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什么是数据库的逻辑结构设计?简述其设计步骤。

问答题
2022-01-12 12:02
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正确答案

数据库逻辑设计的任务是把概念设计阶段产生的E-R图转换为具体DBMS支持的组织层数据模型,这些模式在功能、性能、完整性和一致性约束方面满足应用要求。
关系数据库的逻辑设计一般包含三项工作:
1)将概念结构转换为关系数据模型。 2)对关系数据模型进行优化。 3)设计面向用户的外模式。


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