GML and XQuery based cadastral spatial object query model description and implementation

Taking cadastral feature as example, the spatial object query models based on GML and XQuery are proposed. The cadastral spatial feature models based on GML are first defined. The query models of the cadastral spatial objects are then presented. The topology relationships between these objects are derived. The relation query methods and algorithms between two objects are given in detail. A GML-based cadastral GIS system is further developed based on JAVA, DOM and SAX. The proposed spatial models based on GML and the query technologies based on XQuery are tested through the system, and the results show that it is feasible to implement XQuery to query the relationships between cadastral spatial objects based on GML.