5. 数据库三级模式中，外模式到模式的映像提供了数据的逻辑独立性。（）对错 - 查题网

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国家开放大学 / 数据库应用技术

5. 数据库三级模式中，外模式到模式的映像提供了数据的逻辑独立性。（）

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数据库应用技术

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