Query Optimization in DDBS
Distributed query processing is an important factor in the overall performance of a distributed database system. The database queries access the applications on the distributed database sites thus the main problem incurred is the minimization of the total operating cost i.e. communication cost and processing. The problem gets more complicated by the fact that query processing not only depends on the operations of the query, but also on the parameter values associated with the query. Query optimization is a difficult task in a distributed client/server environment as data location becomes a major factor.