This model decomposes a nested relational schema into a set of atomic schemas, each of them constitutes of a primary key or a primary key plus a non-primary attribute.

此模型将复杂的嵌套关系模式分解为由主键或主键和一个非主属性构成的原子模式集合。

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Based on the concept of relation and sub-relation, this paper investigates the inherent meaning of traditional set operations for the nested relational data model.

本文提出的一个嵌套关系模型支持文本存储和文本检索操作，其中特征文件索引为文本检索提供了技术支持。

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