Spatial query processing in relational databases for geographic information systems

• Main Author: Chua, Caslon
• Format: text
• Language: English
• Published: Animo Repository 1999
• Subjects: Spatial systems; QUERY (Information retrieval system); Geographic information systems; Information retrieval > Geography; Databases; Databases and Information Systems
• Online Access: https://animorepository.dlsu.edu.ph/etd_doctoral/814
• Institution: De La Salle University

This thesis presents a framework for implementing spatial query processing functions within a relational database system without modifications on the database kernel. The objective of this development is to provide simple and low-cost spatial processing capabilities to workgroup servers. This solution integrates neatly with popular desktop GIS/mapping applications, thus introducing spatial data into IT database applications without expensive upgrade or replacement of the current system. The framework is based on a multiple-step spatial query processing strategy wherein operations are executed in successive filtering and refinement steps. The costs of spatial query operations are reduced with the introduction of simpler and more efficient filtering steps. The main goal of the filtering steps is to reduce the number of objects possibly satisfying a given query. An exact test is then performed on the reduced set of objects at the final stage of the query process to produce the final response to the query. The exact test, which is not performed on all objects because of the filter steps, is usually computationally expensive, since it involves the exact geometry of complex objects.