Research On Methods Of Geo-spatial Data Management Based On Open Source Database PostgreSQL

Open Source Database, a kind of basic applications, is being paid more and more attention by database companies and users in respect that its source code is open and its price is low. In GIS industry, therefore, a new field, which is mainly on constructing geo-spatial database by open source database, comes into being. The intention of this research is to bring forward a solution, which can manage geo-spatial data based on open soure database, and to make it come true.First of all, this research discusses different principles of some popular open source databases which support geo-spatial data management. Then PostgreSQL, a kind of open source databases, is chosen as the chief one in this research. After analizing the architecture of PostgreSQL, it goes deeply into PostGIS, the extent module of PostgreSQL, to learn the classes and functions for geo-spatial data support. Then, it designs a spatial database engine called PostSDE, which is according to object-relational data model. PostSDE obeys OpenGIS Simple Features Specification made by OGC and uses object-oriented thinking.PostSDE is implemented and used in developing a basic platform on irrigation works based on Linux supported by the theories and designs above. In one hand, PostSDE uses LIBPQ, one API library of PostgreSQL, to connect with database. Also, it uses OGR library to read and write vector data and manages them as geo-spatial tables in database following the standard library of OGC and PostGIS. In the other hand, PostSDE is used to act as a middleware to make client and database communicate with each other. It can help connect with the database, import shapefile format data into the database and manipulate geo-spatial tables in the database.The related research and application show that open source way can compare commercial way to magage geo-spatial data, for its advantage in cost and capability in requirement. Construction of GIS using open source module must be growing quickly along with the improvement of open source databases.