Optimization for Fusion Query over Internet Databases
Zhang De · Chinese Journal of Computers · 2000
Internet is a large, autonomous distributed systems, whose nodes are increasingly becoming database systems. The new environment facilitated by the Internet requires rethinking many of the concepts in current distributed database technology. This paper investigated the fusion query, which is important in Internet context. After analyzing the algebra features of fusion query, it is found that its optimization is a NP Complete problem. Then the heuristic algorithms with low complexity are proposed, which use “extended semijoin” to reduce communication cost and use “local disjunction, remote conjunction” strategy to reduce respond time.