研究了数据仓库中一般的实视图选取策略,定义一种利益代价图??BC图(BENEFITSCOSTGRAPH),并以BC图为基础给出了选取实视图集的算法.最后,将BC图扩展为BC+图,解决带索引的实视图的选取问题“,”In this paper, the authors propose a general approach to selecting materialized views, and define a structure named BC graph(benefit cost graph) as the basis for selection of materialized views. A algorithm based on BC graph is then presented for such selection. Finally, it extends BC graph to BC + graph to take account of indices associated with views.