Properties of semijoin sequences
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The problem of finding optimum semijoin sequence for an arbitrary query under linear cost function for the transmission cost is NP-hard. Hence heuristic algorithms with desirable properties are explored. In this paper four properties of semijoin programs for distributed query processing are identified. The use of these properties in constructing semijoin sequence is justified. An existing algorithm is modified incorporating these properties. Empirical comparison with existing algorithms shows the superiority of the proposed algorithm.
KeywordsQuery Processing Attribute Size User Site Transmission Cost Assembly Site
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- Black, P.A. and Luk, W.S., A New Heuristic for Generating Semijoin Programs for Distributed Query Processing, IEEE COMPSAC, 1982, 581–588.Google Scholar
- Chung, C. W. and Irani, K.B., A Semijoin Strategy for Distributed Query Optimization, IEEE Int. Conf. on Distributed Computing System, 1984.Google Scholar
- Hevner, A.R., Optimization of Query Processing in Distributed Databases, PhD Dissertation, Purdue University, Lafayette, Indiana, Sept., 1979.Google Scholar
- Hevner, A.R. and Yao, S.B., Query Processing on a Distributed Database, Procs. 3rd Berkeley Workshop on Distributed Data Management and Comp. Networks, August, 1978.Google Scholar
- Goodman, N.et al., Query Processing in SDD-1: A system for Distributed Databases, Tech. Rep. CCA-79-06. Computer Corporation of America, 1979.Google Scholar
- Srinivasan, B., and Ooi, B.C., Optimal Properties of Semijoin Sequences for Distributed Query Processing, Technical Report, National University of Singapore, July, 1987.Google Scholar
- Wong, E., Retrieving Dispersed Data from SDD-1: A System for Distributed Databases, Proc. 2nd Berkeley Workshop on Distributed Management and Computer Networks, May, 1977, 217–235.Google Scholar
- Yu, C.T. and Chang, C.C., On the Design of a Query Processing Strategy in a Distributed Database Environment, Proc. ACM SIGMOD, 1983, 30–39.Google Scholar
- Yu, C.T. and Ozsoyoglu, M.E., An Algorithm for Tree Query Membership of a Distributed Query, IEEE COMPSAC, 1979, 306–312.Google Scholar