Study On Performance Tuning And Optimization Of Spatial Database

With the database technology widespread application in the production, life and all levels of society, it puts forward higher requirements to manage data on the capacity and efficiency by database management system. Based on the existing hardware and software resources, how to make the potential of database management system, fully optimize and enhance the operational effectiveness of the application database, can not only save operating costs, but also protect the database'security, stability and efficiency. In fact, performance tuning and optimization has become an important research subject in database, especially in spatial database applications.Taking the ground fissures and land subsidence disaster spatial database in Fen-wei Basin as the research object, referencing the existing research results in the database performance optimization and adjustment, and combined with the actual situation of the database construction, the paper will take space database storage optimization, Oracle lOg memory and safety parameters adjustment, map service issued as the main research contents, in order to find the general adjustment and optimization strategy and method to improve space database performance. Accordingly, the paper made the research results:Firstly, in order to reduce Oracle storage space, vector data as the feature class directly stored in the SDE Geodatabase model. According to different raster data types, Digital Elevation Model stored in raster dataset, and Digital Orthophoto Model stored in raster catalog after setting compression method and compression ratio, data re-sampling and pyramids series parameters.Secondly, using Oracle own performance optimization and monitoring tools, according to the statistical information of the memory parameters'activities, and referencing certain performance evaluation index, we timely adjust and optimize the system global area and program global area parameters. Meanwhile, we also adjust space database system security parameters, opening space database archivelog model to safeguard the spatial database' security, stability and efficiency.Thirdly, map document are issued for two kinds of maps service by Using the ArcGIS Server:one kind is cache maps service. When change map service into PNG or JPEG data types, set tile levels, and then slice the grid data according to each tile level, storing in the Server's cache path to accelerate data shows; One kind is dynamic map service. It mainly enhances map display effect by setting each layer multistage scale display range. Both of them provide URL for WebGIS using map services, avoiding access spatial database backstage.