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1、DBModelingExamPracticalAnswerthefollowingquestions.1.CreateanE-Rschemaforadatabasesystemusedtomanageaccountinformationatacommunitybank.Thebankhasseveralbrancheswithuniquenames.Acustomermayhaveoneormoreaccountsinoneormorebranches.Anaccountmustbelongtooneandonlyonebranch.Eachaccountisoperatedonbytr
2、ansactions,whichmaybedepositstoorwithdrawalsfromsomeaccount.Thedatabasekeepstrackofallthetransactionsoneachaccount,inadditiontothebalanceofindividualaccountsandtheassetsofindividualbranches.Foreachentity,specifyallitsattributes,primarykey,andalternatekey(s).InyourERschema,besuretocapturethecardin
3、alityconstraintsandparticipationconstraintsofallrelationships.Makereasonableassumptionstocompletethespecification.Explicitlystateallyourassumptions.EVERYconstructinyourERschemashouldbesubstantiatedbyeitherthespecificationaboveoryourexplicitassumptions.2.Thefollowingtablestoresinformationaboutwhic
4、hsupplierscansupplywhichparts.ThetablecapturesthefactthatapartwhosenameisPartNameandwhoseIDisPartIDcanbesuppliedbysupplierswhosenamesareinSupplierNameandwhoseIDsareinSupplierID.Notethatapartcanbesuppliedbymanysuppliers,andasuppliercansupplymanyparts.CAN_SUPPLYPartIDPartNameSupplierIDSupplierName1
5、234Nut223ProMetal1234Nut224Biscayne2134Bolt223ProMetal3.Performthefollowingtasks.1.Listtheprimarykey.2.ListalltheFDs.3.Whatnormalformistherelationin?Explain.4.Applynormalizationtoitincrementally,carryingthenormalizationprocessthrougheachofthehighernormalformspossibleupto3NF.Thatis,iftherelationwe
6、reunnormalized,bringittofirstnormalform,thenbringthefirstnormalformyou'vejustcreatedtosecondnormalform,andthenbringthesecondnormalformtothirdnormalform.ForeachtransformationtothenexthighernormalformX,§ExplainthestepsyoutooktobringittothenormalformX.§ProvidethenormalformX'stablestructure,primaryke
7、y(s),andtheFDs.§ExplainwhyyouthinkitisinthenormalformX.Forexample,ifyouthinkthereisapartialdependency,fullydefendyourconclusionbyexplaininghowacolumnispartiallydependentonsomeothercolumn(s).Thatis,iftherelationwereinan