Distributed query processing in a relational data base system
Robert S. Epstein, Michael R Stonebraker, Eugene Wai Leong Wong · 1978
In this paper we present a new algorithm for retrieving and updating data from a distributed relational data base. Within such a data base, any number of relations can be distributed over any number of sites. Moreover, a user supplied distribution criteria can optionally be used to specify what site a tuple belongs to.The algorithm is an efficient way to process any query by "breaking" the qualification into separate "pieces" using a few simple heuristics. The cost criteria considered are minimum response time and minimum communications traffic. In addition, the algorithm can optimize separately for two models of a communication network representing respectively ARPANET and ETHERNET like networks. This algorithm is being implemented as part of the INGRES data base system.