Integration of heterogeneous geospatial data in a federated database

The integration of heterogeneous geospatial data offers possibilities to manually and automatically derive new information, which are not available when using only a single data source. Furthermore, it allows for a consistent representation and the propagation of updates from one data set to the other. However, different acquisition methods, data schemata and updating cycles of the content can lead to discrepancies in geometric and thematic accuracy and correctness which hamper the combined integration. To overcome these difficulties, appropriate methods for the integration and harmonization of data from different sources and of different types are needed. In this paper we describe two generic cases including novel integration algorithms, namely the integration of two heterogeneous vector data sets, and the integration of raster and vector data. Both algorithms are linked to a federated database which allows for automatic object matching and for managing n:m relationships. We describe and illustrate our work using vector data from topography and the geosciences, as well as multi-spectral imagery.