Issue No. 08 - August (1982 vol. 31)
null To-Yat Cheung , Department of Computer Science, University of Ottawa
A simple and efficient method for processing general equijoin queries in a distributed relational database is described. The query is first decomposed into a set of simple queries, each being involved with only one of the joining domains and its relevant equijoins. An extended version of Hevner and Yao's STRATEGY PARALLEL or STRATEGY SERIAL is then applied on each of them for generating transmission schedules. These schedules will fully reduce (with respect to a simple query) some specified relations. The latter are then transmitted to the result site for final processing. In the case of minimizing total time, our method has a lower order of complexity than ALGORITHM GENERAL studied by Hevner and Apers. Examples show that our method gives better and more efficient solutions than theirs.
semijoin transmissions, Distributed relational databases, general equijoin queries
n. To-Yat Cheung, "A Method for Equijoin Queries in Distributed Relational Databases," in IEEE Transactions on Computers, vol. 31, no. , pp. 746-751, 1982.