RDBMS is based on firm mathematics set theory with simple and clear data structure, and powerful query function, so it has become the basic technology for realization of information system.

因为RDBMS是建立在严格的数学集合论基础上的，数据结构简单、清晰，具有强大的查询能力，RDBMS成为实现信息系统的基本技术。

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Besides the traditional functions, such as spatial information display, query, analysis, the system has the features of real-time positioning and navigation by the GPS technology.

该系统除了具有传统的空间信息显示、查询、分析等功能外，还利用现在迅速兴起的GPS定位技术，实现实时的定位导航功能。

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This paper puts forward an information retrieval system based on XML documents database on the foundation of segmentation technology, index technology and structured query language technology.

在分词技术、索引技术、结构化查询语言技术的基础上，提出了一个基于XML文档数据库的信息检索系统，这一系统模型主要由分词模块、索引模块及查询模块组成。

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