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Return to Aggregates A temporal aggregation query is an important but costly operation for applications that maintain time-evolving data (data warehouses, temporal databases, etc.). Due to the large volume of such data, performance improvements for temporal aggregation queries are critical. In this paper we examine techniques to compute temporal aggregates that include keyrange predicates (range temporal aggregates). In particular we concentrate on SUM, COUNT and AVG aggregates. This problem is novel; to handle arbitrary key ranges, previous methods would need to keep a separate index for every possible key range. We propose an approach based on a new index structure called the Multiversion SBTree, which incorporates features from both the SBTree and the Multiversion BTree, to handle arbitrary keyrange temporal SUM, COUNT and AVG queries. We analyze the performance of our approach and present experimental results that show its efficiency. ![]() DiSC'02 © 2003 Association for Computing Machinery |