A Spatio-temporal Database System Based on TimeDB and Oracle Spatial

The importance of the spatial component of data items has been long recognized and gave rise to a successful line of research and development in Geographic Information Systems (GIS). In many application domains it is also essential to deal with the evolution of data along time and to integrate spatial, temporal and other aspects of the information domain in an expressive and operationally effective manner. Until recently, temporal solutions provided by spatial database systems were semi-temporal approaches lacking full temporal support. As a consequence, most spatial database systems manage snapshots of the present state of facts without fully exploiting historical temporal aspects. This paper provides preliminary results on a spatiotemporal database implementation. The proposed system builds on existing database technologies, TimeDB and Oracle Spatial, for temporal and spatial support, respectively. The justification for the choice of these technologies is given, based on the state of the art in spatial and temporal database research. The integration of the spatial and temporal components is achieved with the extension of the TimeDB implementation layer. A set of goals has been established in order to cover both the integration of the spatial support and the enforcement of the temporal requirements in the extended system. Issues and solutions are presented and illustrative examples show the use of the implemented functionalities.