After the conceptual schema comes the logical schema — the data model that defines the concepts with greater detail and shows the relationships between the entities.
在概念模式后出现的是逻辑模式——用更多的细节定义概念，并显示实体之间的关系的数据模型。
When you use a conceptual model to describe the data in a database, you can query data through your objects instead of having to translate back and forth between a database schema and an object model.
当您使用概念模型来描述资料库中的资料时，可以透过物件查询资料，而不需要在资料库结构描述和物件模型之间来回转译。
When you use a conceptual model to describe the data in a database, you can query data through your objects instead of having to translate back and forth between a database schema and an object model.
当您使用概念模型来描述资料库中的资料时，可以透过物件查询资料，而不需要在资料库结构描述和物件模型之间来回转译。
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