DocumentCode :
3063735
Title :
Constraint database query evaluation with approximation
Author :
Veltri, Pierangelo
Author_Institution :
Inst. Nat. de Recherche en Inf. et Autom., Le Chesnay, France
fYear :
2001
fDate :
36982
Firstpage :
634
Lastpage :
638
Abstract :
Considers the problem of solving a large number of simple systems of linear constraints. This problem occurs in the context of constraint databases. The developed methodology is based on a hierarchical evaluation of the constraints, which are first simplified and replaced by approximations. We focus on systems of linear constraints over the reals, which model spatial objects, and we consider both geometric and topological approximations, defined with very simple constraints. We show that these constraints can be used either to solve the initial systems, or at least to filter out unsatisfiable systems. The main contribution of the paper is the development of a set of rewriting rules that allow the transformation of spatial object queries into equivalent ones that make use of the approximation, reducing the query evaluation cost
Keywords :
approximation theory; computational geometry; constraint theory; database theory; query processing; rewriting systems; topology; visual databases; constraint database query evaluation; geometric approximations; hierarchical evaluation; linear constraints; query evaluation cost; real numbers; rewriting rules; spatial object modelling; spatial object query transformation; topological approximations; unsatisfiable system filtering; Animation; Constraint optimization; Costs; Filters; Geometry; Image databases; Logic programming; Query processing; Solid modeling; Spatial databases;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Information Technology: Coding and Computing, 2001. Proceedings. International Conference on
Conference_Location :
Las Vegas, NV
Print_ISBN :
0-7695-1062-0
Type :
conf
DOI :
10.1109/ITCC.2001.918868
Filename :
918868
Link To Document :
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