A spatial model for complex objects with a broad boundary supporting queries on uncertain data

This paper proposes a new data model for spatial databases that supports spatial entities with a broad boundary. The model is proposed as a solution to the problem of handling uncertainty in spatial data. Broad boundaries absorb all the uncertainty by which spatial data are commonly affected and allow computations in presence of uncertainty without rough simplifications of the reality. A specific model for topological relations between regions with a broad boundary is then developed and hierarchically structured topological operators are proposed. Such operators allow users to progressively refine their queries and constitute the basis for a spatial extension to SQL. The model proposed in the paper can be easily integrated into existing data models for spatial databases.