Index Structures for Databases Containing Data Items with Set-valued Attributes Index Structures for Databases Containing Data Items with Set-valued Attributes
نویسنده
چکیده
We introduce two new hash-based index structures to index set-valued attributes. Both are able to support subset and superset queries. Analytical cost models for the new index structures as well as for the two existing index structures, sequential signature le and Russian Doll Tree, are presented and experimentally validated. Using the validated cost model, we express the performance of all four index structures in terms of the performance of the sequential signature le. This allows a direct analytical comparison of their performance. Last, we report on our benchmark results comparing the real performance of all four index structures. We especially investigate their performance for skewed data.
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