XML结构和数据库表之间的映射关系是建立在一组映射规则上的。

The mapping between the XML structure and the database table is based on a set of simple mapping rules. The following XML fragment illustrates the mapping rules

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该模型为本体中的类定义了访问规则和访问控制属性，并由此建立了访问控制关系。

In this model, the access rules and the access control attributes are defined. The relations for the access control are set up.

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数据库规范化是一种基于规则的，施加于数据结构之上的数据设计和组织过程，这种规则有助于建立关系型数据库。

Database normalization is a data design and organization process applied to data structures based on rules that help building relational databases.

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