To achieve acceptable query reposnse time sin data warehouse environments,the data have to be pre-aggreagated according to the need of the applicaitons and stoed reqdundantly.These materialized vies must be kept up to data,to assure their usabiluity .in this paper we present an algoirhtm which improves the maintenance of mateiralized views in tow ways.in the ifrst palxe,the maintenance process is accelerated by supporting differnet maintenance strateiges for individual views.Thus,ivews which do not need to be up to date cna be maintanied in a deerred or periodical way.In the second palce,the alogirthm provides session ocnsistency,assuring htat during an OLAP-session the undrlying data do not change form the user's point of view,the algorihtm vfacilitates high flexibility and performanc eof view maintenance without compromising session consistency.
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