Distributed query processing in the Internet: exploring relation replication and network characteristics

We introduce the concept of network graph for distributed query processing. Semijoins and joins are termed contributive replicated semijoins and contributive replicated joins, respectively, when they are interleaved into a join sequence to reduce the amount of data transmission cost required in a network with replicated relations. Our solution procedure consists of three consecutive steps, namely relation selection, join sequence scheduling and merge processing. A simulator is developed to evaluate the performance of algorithms devised. Our results show that the approach of interleaving a join sequence with contributive replicated semijoins/joins is not only efficient in its execution but also effective in reducing the total amount of data transmission cost required to process distributed queries.