Partition strategy for distributed query processing in fast localnetworks

A partition-and-replicate strategy for processing distributed queries referencing no fragmented relation is sketched. An algorithm is given to determine which relation and which copy of the relation is to be partitioned into fragments, how the relation is to be partitioned, and where the fragments are to be sent for processing. Simulation results show that the partition strategy is useful for processing queries in fast local network environments. The results also show that the number of partitions does not need to be large. The use of semijoins in the partition strategy is discussed. A necessary and sufficient condition for a semijoin to yield an improvement is provided