Abstract: Distributed database is a collection of logically related databases that cooperate in a transparent manner. Query processing uses a communication network for transmitting data between sites. It refers to one of the challenges in the database world. The development of sophisticated query optimization technology is the reason for the commercial success of database systems, which complexity and cost increase with increasing number of relations in the query. Mariposa, query trading and query trading with processing task-trading strategies developed for autonomous distributed database systems, but they cause high optimization cost because of involvement of all nodes in generating an optimal plan. In this paper, we proposed a modification on the autonomous strategy K-QTPT that make the seller’s nodes with the lowest cost have gradually high priorities to reduce the optimization time. We implement our proposed strategy and present the results and analysis based on those results.
Abstract: Appeared toward 1986, the object-oriented databases
management systems had not known successes knew five years after
their birth. One of the major difficulties is the query optimization.
We propose in this paper a new approach that permits to enrich
techniques of query optimization existing in the object-oriented
databases. Seen success that knew the query optimization in the
relational model, our approach inspires itself of these optimization
techniques and enriched it so that they can support the new concepts
introduced by the object databases.