Previous multidimensional dynamic hashing schemes exhibit two obvious shortcomings. First, even for uniform record distribution, the retrieval performance of these schemes suffers from several disadvantages. In a recent paper we have suggested a multidimensional dynamic hashing scheme which exhibits better retrieval performance than its competitors for uniform distribution. The even more severe second disadvantage of all known multidimensional dynamic hashing schemes is the very poor performance for non-uniform record distributions. In this paper we present the quantile method as a scheme which exhibits for non-uniform distributions practically the same performance as for uniform distributions. This is underlined by experimental runs with an implementation of our scheme. In addition to its excellent performance, our scheme fulfills all the necessary requirements to be used in an engineering database system: it is dynamic, is suitable for secondary storage devices, supports point data and spatial data objects and supports spatial clustering (proximity queries).
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