Pre - Processing Queries with Spatial Constraints
نویسنده
چکیده
This paper discusses strategies for pre-processing spatial queries before executing them in a geographic database. A computational method has been devised, which is capable of assessing whether or not a spatial query is consistent, i.e., that its constraints are free of any selfcontradictions. If the query is inconsistent, it can be rejected immediately without a need to process it in the database. The query evaluation is based on algebraic properties of spatial relations such as symmetry, converseness, transitivity, and composition and employs constraint propagation in a constraint network to detect conflicts. Examples are given for how this method works for spatial queries with constraints about topological relations, for which a comprehensive algebraic formalization exists.
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