WPERF+:An Efficient Optimization Algorithm for Distributed Query

The constant development of computer hardware and internet have encouraged the decen- tralization of data, which increases the needs to access data from different sites. Distributed query is a query process that will incur heavy communication cost. The basic challenge is to design and develop efficient query strategies and techniques to minimize this communication cost. An efficient optimization algorithm for distributed query, i.e., WPERF+, is presented in this paper. The advantages of W semi- joins and PERF joins have been combined into the WPERF+, and greatly enhanced the performance of W semi-joins and PERF joins. In this paper, it is theoretically proved that the WPERF+ strategy is an efficient optimization algorithm that can greatly reduce its communication cost of distributed query.