GIS Data Model and Its Architecture
地理信息系统的数据模型与系统结构

Data model is a representation of data and its relation. It is consi-dered very important in database design. In constrast to alphanumerical data, spati- al data is characterised by its large magnitude and complexity.Therefore,it is ofsignificance to do research on spatial data model.Most commericial GISes are basedon relational data model.However,its drawbacks on representing spatial entitiesand their interrelations have led to the separation of graphic database and attributedatabase. In order to overcome this problem,extended relational data model andobject-oriented data model are explored.This paper introduces these three data mo-dels and their corresponding GIS architecture,analyses their pros and cons, and pre- sents the relation between spatial data model and GIS architecture.