資源描述：
《數(shù)據(jù)倉庫物化視圖在線算法研究》由會員上傳分享，免費(fèi)在線閱讀，更多相關(guān)內(nèi)容在學(xué)術(shù)論文-天天文庫。
1、東南大學(xué)博士學(xué)位論文數(shù)據(jù)倉庫物化視圖在線算法研究姓名：張柏禮申請學(xué)位級別：博士專業(yè)：計算機(jī)應(yīng)用技術(shù)指導(dǎo)教師：孫志揮20050701AbstractAdatewarehouseisadatarepository,whichcollectsandmaintainsalargemountofdatafrommullipledism'buted，autonomousandpossiblyheterogeneousdatasoIM．Oftenthedataisstoredintheformofmaterializedview3forthepurposeefficientlyimpl
2、ementingdccision-suppo仳orOLAPqueries．Firstly,theselectionofviewsformaterializationisoneofthemostissuesinthedesigndatewarehouse,it’sgoalistoselect∞appropriatesetofviewsthatminimizestotalqueryresponsetimeand／orthecostofmaintainingtheselectedviews,givonalimitedamountofrasonsce，e．g．，storagesp
3、ace，materializationtime，ortotalviewmaIntanancetime．Secondly,maintaininglotsofmaterializedviewsischallenging．especiallyffthedatasources2reautonomousandviewsofthedataatthedatawarehousespanmultiplesoume“q．Theviewshavetobemaintainedintimetoreflecttheupdatesdoneagainstthebaserelationsstoredatt
4、hevariousdatesources．n圮e伍cientmaintenanceofmaterializedviewshasbecomeanotherimportantresearchiss∞．Theusualmethodsis廿扭tthematerializedviewsaraselectedandmaintainedoffline。forexample,thestaticselectionalgorithmofviewisemployedtogenerateorregeneratethematerializedviewset，andbatchupdatepolicy
5、isusedtomaintainthematnight，However,wheremtheamountofdataenteringawerchousc,thequeryloads，andtheneedtoobtain叩-to-dateresponsesareauincreasing,the‘'night"’timeavailableformakingthewarehouseup-to-dateisshrinking．Theseu'andsnecessitateefficientonlinealgorithmsformaterializedviews．Inthispaper
6、,itisemphasizedtomakedeeperresearchontheselectionalgorithmsandmaintenancealgorithmsofmaterializedviewsduringthedatawarehouseon-line．Themaincontributionsofthisdissertationareasfollows：(1)Tosolvetheshortageofthestaticselectionalgorithmofmaterializedview,thepaperpresentsPMVS．preprocessorofma
7、terializedviewselectionapproach．PMVSmakesu∞ofthequerysparsenessanddatasparsenassinmulti-dimensionaldatasets，andreducesthetimecomplex(searchspacc)ofthestaticselectionalgorithm，Sothecostofstaticalgorithmsonspaceandtimecanbecutdowntofitforonlinedemand．(2)Preseataimprov
