Query Optimization in Distributed Data Base Systems

Query optimization is a difficult task in a distributed client/server environment as data location becomes a major factor. In order to optimize queries accurately, sufficient information must be available to determine which data access techniques are most effective. Optimization algorithms have an important impact on the performance of distributed query processing.. Various algorithms are used for query optimization which have minimal response time and minimal total time, for a special class of queries. The optimal algorithms are used as a basis to develop a general query processing algorithm. The integration of a query processing subsystem into a distributed database management system is used for analyzing query response time across fragmentations of global relations. Optimization algorithms have an important impact on the performance of distributed query processing