Representation of CityGML instance models in BaseX

Abstract

The Open Geospatial Consortium standard CityGML is an application schema of GML 3.1.1 for the representation, storage and exchange of semantic-rich virtual 3D city models. Here we assess the feasibility of storing, querying and updating CityGML models in the native XML database system BaseX. The features and performance of BaseX are compared with the implementation of the 3DCityDatabase which stores CityGML models in a relational database system. The results show that BaseX is a fast, flexible and intuitive tool to store and query even large CityGML documents. Its main advantage is the schema-oblivious storage mechanism that allows schema changes without changes to the database layout and the fast import and export of CityGML models. Using the 3DCityDatabase to manage CityGML data on the other hand is a better choice when spatial analysis and integration with third party software are demanded.