Optimization of n-way Spatial Joins Using Filters

摘要

This paper discusses techniques in the context of supporting a GeographicInformation System. It is known that the use of filters on geometric objects has a significant impact on the processing of 2-way spatial join queries. The index is used to reduce the cost of the filter step and to minimize the cost of retrieving geometric objects from disk. In this article, we focus on the criteria for comparing filters and not on those for spatial indices. Important aspects of a multi-step filter-based n-way spatial join method are described together with performance experiments. The winning join method uses several filters with approximations that are constructed by rotating two parallel lines around the object. (Copyright (c) University of Twente 1995.)