A data schema and its query for modeling dynamic geographical world

Researchers are paying more attention to the evolving nature phenomena with the development of spatiotemporal database modeling methods. However most of the researches have been focused on the treatment of discrete changes in spatial objects. Based on the study of versions, events and processes, which is introduced in another paper [S. Wang et al., 2005], we proposed a relational data schema to describe spatiotemporal phenomena. The data schema is adapted for the storage of continuous evolving information instead of discreet patterns. Its framework allows the representation of entities and processes within a GIS database and enable the expression of spatial queries related to changes in both space and time. The query called STFQL was discussed in detail to allow users to ask for changes in spatiotemporal relationships.