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Spatial database operations are typically performed in two steps. In the filtering step, indexes and the minimum bounding rectangles (MBRs) of the objects are used to quickly determine a set of candidate objects. In the refinement step, the actual geometries of the objects are retrieved and compared to the query geometry or each other. Because of the complexity of the computational geometry algorithms...
In this paper, we explore the possibility of transforming queries with minimum and maximum predicates into equivalent queries that can be computed more efficiently. The main contribution of the paper is an algorithm for propagating min and max predicates while preserving query equivalence under certain monotonicity constraints. We show that the algorithm is correct and that the transformed query...
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