Towards a visual query language for an object oriented geographical information system

Abstract

A query language designed for a geographical information system is described and discussed. The basic map data structure is objected-oriented, homogeneous, and raster-based. Because of the homogeneous map data structure, queries can be applied in a more or less generic way; that is, queries can be applied to all map data structures regardless of their type. The query language design is based on a visual interaction technique that gives a simpler structure compared to conventional query languages. The various types of queries are discussed.<>