An object-oriented data model and a query language for geographic information systems

We present a new extensible, object-oriented data model for geographic information systems and a corresponding extensible SQL-like query language. This model is intended to be a general base for the development of geographic information systems. Hence, our model supports both two- and three-dimensional data as well as raster- and vector-based data. In addition, the objects may have several thematic and geometric attributes. Basically we propose a hierarchy of classes describing so called spatial objects. Classes required to describe a concrete application are modelled as subclasses of these abstract classes. The presented query language generalizes earlier proposals of SQL-like query languages for geographic information systems. (orig.)Available from TIB Hannover: RO 7057(1995,15) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman