Design And Implementation Of Webgis Massive Tile Data Management Engine

With the rapid development and application of WebGIS, static cache technology of WebGIS data visualization has also been widely adopted. However, massive tile data produced during static cache data processing bring heavy burden to data management. At present there are not formed a unified and efficient method for massive tile data management. Two methods are generally used, namely directory structure-based discrete file management and relational database based maintenance management, but there are complex maintenance, low operation efficiency and existence safety hidden troubles. This paper discusses tight structured tile data management and maintenance based on commercial management of such data together with tile data’s particularity. The paper focuses on the discussion and the design of the following aspects:1) The paper analyzes tile data generation and characteristics. The paper discusses how WebGIS schedules topographic and image data as well as image pyramid based tile data generation and scheduling and discusses the characteristics of tile data, common management methods in WebGIS as well as problems of such management, put forward existing management methods of massive tile data management based on tight structured data, and analyzes key issuses to be solved in engine development.2) The paper also discusses tightening methods of massive tile data. The design adopts a data management of respective storage of tile tightening data files and corresponding tile data retrieving information to achieve Block-unit tightening tile data structure design as well as the design of retrieving data structure of corresponding tile data retrieving information management. Data structure based design analyzes the mechanism of updating and maintenance of Block structured tile data increment.3) The design of engine’s logic structure is achieved based on tightening data structure. And detailed analysis is also given to the internal and repository structures of engine underlying interface repository, which realizes the encapsulation of engine underlying interface. With engine underlying interface repository, engine visualized data management module and Web Service technology based tile data service module are respectively designed and achieved. And FastCGI based efficient tile data services are also designed and achieved via shared index. In the meanwhile, maintenance of massive tile data visualization is realized with graphical interface.4) Finally, the paper experimentally verifies the efficiency, convenience and maintenance of engines in massive tile data maintenance.