Research On WebGIS System Based On Native XML Database

WebGIS, which is an important field of GIS research, is a new technology which combines the internet technology with GIS, and extends and improves the functionality of GIS. However, the WebGIS systems developed by many domestic and foreign corporations are all using their own data formats and methods of managing spatial data information, which makes it difficult to have data shared between each other. But this problem is fixed by XML and related specifications.GML (Geographic Markup Language) is proposed by OpenGIS Consortium to facilitate the interoperation of WebGIS system, which is an XML specification for the expression of spatial geography information. At present there are two main methods to manage the XML formatted GML data: XML-Enabled Database(XED) and Native XML Database(NXD). After analyzing the benefits and drawbacks of both the two kinds of XML databases in managing XML data, this thesis explored the technology and method of managing GML data using Native XML Database, including the storing, querying and modifying of GML documents. Besides, the SVG-based technology of WebGIS map publishing was researched , as well as the transforming of GML to SVG using XSLT(eXtensible Stylesheet Language: Tranform). Finally, taking Jiangsu Traffic Accident Information WebGIS system for example, the thesis introduced some key parts of the implementation of Native XML Database based WebGIS system.