SVIQUEL: A Spatial Visual Query and Exploration Language

The need to analyze and query spatial data is becoming increasingly important with the advent of applications such as Geographic Information Systems, Image Databases and Remote Sensing. The focus of our research is to support spatial data analysis by developing a direct manipulation environment to visually query as well as browse spatial data and to review the visual results for trend analysis. In this paper, we present a visual query language (SVIQUEL) which allows us to specify the relative spatial position (both topology and direction) between objects using direct manipulation. This query language builds upon the notion of dynamic query filters and significantly extends them to support integrated querying of both topological and directional types of spatial data. In order to facilitate continuous querying as required by a direct manipulation environment, we designed an integrated neighborhood model for both kinds of spatial relationships (topology and direction). Our spatial query p..