Selecting views to materialize impacts on the efficiency as well as the total cost of establishing and running a data warehouse. One of the most important decisions in designing a data warehouse is selection of right views to be materialized. This problem is to select a right set of views that minimizes total query response time and the cost of view maintenance under a storage space constraint. In this paper, according to our practical application, the factor that refrains us from materializing all views in the data warehouse is not the space constraint but query response time. For queries fast answers may be required. So we develop algorithms to select a set of views to materialize in data warehouse in order to minimize the total view maintenance time under the constraint of a given query response time. We call it query-cost view select problem. First, we design algorithms for query-cost view select problem, we give view node matrix in order to solve it. Second , we use experiments do demonstrate the power of our approach . The results show that our algorithm works better in practical cases. We implemented our algorithms and a performance study of the algorithms shows that the proposed algorithm delivers an optimal solution. Finally, we discuss the observed behavior of the algorithms. We also identify some important issues for future investigations.
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