Research On Technologies Of Rules In Spatial Database

Along with the rapid development of aerospace and photogrammetry, spatial data have been increasing sharply in number and size. Spatial database management system (SDBMS) is a very important means to store and manage spatial data. In order to store, manage and utilize spatial data much more efficiently, the capabilities of all aspects of SDBMS need to be improved.Under this circumstance, the industry and the department holding massive spatial data should consider how to provide services to user'actively'. In spatial databases, the rule technologies are used to achieve spatial data integrity constraints. Besides, spatial database management systems need to support long transaction in cooperative editing of spatial data based on web services, and spatial rules is the key component to achieve long-transaction management. The technologies of spatial rule can also be used in the applications of active services of geographic information by defining and implementing business rules with spatial characteristics. In addition, it can improve the compatibility between different spatial databases by expanding and optimizing spatial rule technology. Consequently, the technology of spatial database supporting rules is of great importance for development and application of Geographic Information System (GIS).This paper focuses on the reserch on technology of spatial database rules. First of all, the model of spatial rules, combining with the spatial characteristics of a spatial data, is created based on ECA rules. Secondly, we designe and implemente a spatial data GSQL paser which support parse the extended spatial components of spatial rules in case of multi-user access in parallel.The parser adoptes the variable-length memory pool technology suitable for spatial data parsing to manage memory. Then, a concurrent access control model is designed and implemented based on the variable-length memory pool technology. The GSQL parser is experimently stable and efficient. Thirdly, we propose a correction algorithm based on relationship graph, as well as an algorithm based on trigger path to improve the accuracy of spatial rule termination analysis. Lastly, the technology of spatial rules is implymented in SDBMS. We use technology of spatial rules to achieve the auto-registration and auto-unregistration of spatial metadata, consistency maintenance of raster data and expansion of long trasaction in SDBMS. In addition, we present the applied pattern of location-based services (LBS) based on spatial business rules and the framework of WFS-T services.