空间数据模型和数据管理是地理信息系统(GIS)最重要的研究领域之一。该文介绍一体化的数据模型-扩展关系模型和以此为基础的,由作者设计的GIS软件原型系统-GEODBMS。GEODBMS使用统一的数据库管理系统(DBMS)同时管理图形和属性数据;使用改进的四叉树-交叠四叉树索引空间目标;使用扩展的SQL语言进行空间查询;使用数据恢复和并发控制方法来加强分布式环境下数据的安全性和一致性维护。

Data modeling and management are active areas in GIS research This paper presents an integrated data model--extended relational model,which underlies the GIS software-GEODBMS is abased GEODBMS manages spatial data including graphics and attributes through a single relational DBMS Its storage model employs the overlapping quadtree,an improved quadtree,as the spatial index structure to facilitate spatial data querying with an extended SQL GEODBMS's data management functions ensure secure data access and provide recovery and concurrency control for transactions in multi-user environment.