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重庆邮电大学学报(自然科学版) 2007
A graph based sliding window multi join over data streamKeywords: data,stream,sliding,window,query,optimization,graph,theory Abstract: Joinoperationisacriticalproblemwhendealingwithslidingwindowoverdatastreams.Therehavebeenmanyoptimizationstrategiesforslidingwindowjoinintheliterature,butasimpleheuristicisalwaysusedforselectingthejoinsequenceofmanyslidingwindows,whichisineffectively.Thegraphbasedapproachisproposedtoprocesstheproblem.Theslidingwindowjoinmodelisintroducedprimarily.Inthismodelvertexrepresentjoinoperatorandedgeindicatedthejoinrelationshipamongslidingwindows.Vertexweightandedgeweightrepresentthecostofjoinandthereciprocityofjoinoperatorsrespectively.Thengoodqueryplanwithminimalcostcanbefoundinthemodel.Thusacompletejoinalgorithmcombiningsettingupmodel,findingoptimalqueryplanandexecutingqueryplanisshown.Experimentsshowthatthegraphbasedapproachisfeasibleandcanworkbetterinaboveenvironment
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