TR-193: Realizing a Spatial Topological Data Model in a Relational Database Management System

Abstract

A Spatial Topological Data Model is presented for defining spatial entities and the rela­tionships between them. The spatial entities are assumed to be vector encoded. The model is specialized for defining the geographic features in geographic information system. It is first described using an Entity Relationship diagram (ER-diagram). This is then translated, in a consistent manner, into a set of relational schemes. Although the paper focuses on the use of a relational database management system to represent a spatial topology model for vector data, the diagram can equally well be translated into a collection of object classes for an eventual implementation in an object oriented database. The model is simple, flex­ible, extendible and non-redundant. By maintaining sites of GIS databases that adhere to the proposed modeling technique, distributed processing in a network of heterogeneous GIS database can be easily achieved. Attribute information is easily associated to the defined spatial entities in a simple manner using the relational join operation.