DW 2.0 The Architecture for the Next Generation of Data Warehousing英文文献资料

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1、DedicationforLynnInmon,mywifeandpartnerPPRELIMS-P374319.inddvRELIMS-P374319.inddv55/27/20085:55:30PM/27/20085:55:30PMPrefaceDatawarehousinghasbeenaroundforabout2decadesnowandhasbecomeanessen-tialpartoftheinformationtechnologyinfrastructure.Datawarehousin

2、goriginallygrewinresponsetothecorporateneedforinformationnotdata.Adatawarehouseisacon-structthatsuppliesintegrated,granular,andhistoricaldatatothecorporation.Butthereisaproblemwithdatawarehousing.Theproblemisthattherearemanydiffer-entrenditionsofwhatadat

3、awarehouseistoday.Thereisthefederateddatawarehouse.Thereistheactivedatawarehouse.Thereisthestarschemadatawarehouse.Thereisthedatamartdatawarehouse.Infactthereareaboutasmanyrenditionsofthedataware-houseastherearesoftwareandhardwarevendors.Theproblemisthat

4、therearemanydifferentrenditionsofwhattheproperstructureofadatawarehouseshouldlooklike.Andeachoftheserenditionsisarchitecturallyverydifferentfromtheothers.Ifyouweretoenteraroominwhichaproponentofthefeder-ateddatawarehousewastalkingtoaproponentoftheactived

5、atawarehouse,youwouldbehearingthesamewords,butthesewordswouldbemeaningverydifferentthings.Eventhoughthewordswerethesame,youwouldnotbehearingmeaningfulcommuni-cation.Whentwopeoplefromverydifferentcontextsaretalking,eventhoughtheyareusingthesamewords,there

6、isnoassurancethattheyareunderstandingeachother.Andthusitiswithfirst-generationdatawarehousingtoday.IntothismorassofconfusionastowhatadatawarehouseisorisnotcomesDW2.0.DW2.0isadefinitionofthenextgenerationofdatawarehousing.Unlikethetermdatawarehouse,DW2.0has

7、acrisp,well-definedmeaning.Thatmeaningisidentifiedanddefinedinthisbook.TherearemanyimportantarchitecturalfeaturesofDW2.0.Thesearchitecturalfeaturesrepresentanadvanceintechnologyandarchitecturebeyondfirst-generationdataware-houses.Thefollowingaresomeoftheimpo

8、rtantfeaturesofDW2.0discussedinthisbook:■Thelifecycleofdatawithinthedatawarehouseisrecognized.First-generationdatawarehousesmerelyplaceddataondiskstorageandcalleditawarehouse.Thetruthofthematteristhatdataonceplacedinadataw