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 sp atial entities with a broad boundary. The model is proposed as a solution t o the problem of handling uncertainty in spatial data. Broad boundaries abs orb all the uncertainty by which spatial data are commonly affected and all ow computations in presence of uncertainty without rough simplifications of the reality. A specific model for topological relations between regions wi th a broad boundary is then developed and hierarchically structured topolog ical operators are proposed. Such operators allow users to progressively re fine their queries and constitute the basis for a spatial extension to SQL. The model proposed in the paper can be easily integrated into existing dat a models for spatial databases. (C) 2001 Elsevier Science B.V. All rights r eserved.