Date Added: Apr 2010
Minimization of query execution time is an important performance objective in distributed databases design. While total time is to be minimized for On Line Transaction Processing (OLTP) type queries, response time has to be minimized in Decision Support type queries. Thus different allocations of subqueries to sites and their execution plans are optimal based on the query type. The authors formulate the subquery allocation problem and provide analytical cost models for these two objective functions. Since the problem is NP-hard, they solve the problem using Genetic Algorithm (GA).