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2、Exercise2.2.1aForrelationAccounts,theattributesare:acctNo,type,balanceForrelationCustomers,theattributesare:firstName,lastName,idNo,accountExercise2.2.1bForrelationAccounts,thetuplesare:(12345,savings,12000),(23456,checking,1000),(34567,savings,25)ForrelationCustomers,thetuplesare:(Robbi
3、e,Banks,901-222,12345),(Lena,Hand,805-333,12345),(Lena,Hand,805-333,23456)Exercise2.2.1cForrelationAccountsandthefirsttuple,thecomponentsare:123456àacctNosavingsàtype12000àbalanceForrelationCustomersandthefirsttuple,thecomponentsare:RobbieàfirstNameBanksàlastName901-222àidNo12345àaccountE
4、xercise2.2.1dForrelationAccounts,arelationschemais:Accounts(acctNo,type,balance)ForrelationCustomers,arelationschemais:Customers(firstName,lastName,idNo,account)Exercise2.2.1eAnexampledatabaseschemais:Accounts(acctNo,type,balance)Customers(firstName,lastName,idNo,account)Exercise2.2.1fAsu
5、itabledomainforeachattribute:acctNoàIntegertypeàStringbalanceàIntegerfirstNameàStringlastNameàString
6、idNoàString(becausethereisahyphenwecannotuseInteger)accountàIntegerExercise2.2.1gAnotherequivalentwaytopresenttheAccountrelation:acctNobalancetype3456725savings234561000checking1234512000s
7、avingsAnotherequivalentwaytopresenttheCustomersrelation:idNofirstNamelastNameaccount805-333LenaHand23456805-333LenaHand12345901-222RobbieBanks12345Exercise2.2.2Examplesofattributesthatarecreatedforprimarilyservingaskeysinarelation:UniversalProductCode(UPC)usedwidelyinUnitedStatesandCanada
8、totrackproductsinstores.SerialNumbersonawidevarietyofproductstoallowthemanufacturertoindividuallytrackeachproduct.VehicleIdentificationNumbers(VIN),auniqueserialnumberusedbytheautomotiveindustrytoidentifyvehicles.Exercise2.2.3aWecanorderthethreetuplesinanyof3!=6ways.Also,thecolumnscanbeor
9、deredinanyof3!=6ways.Thus,thenumberofpresentationsis6*6=36.Exercise2.2.3bWecanorderthethreetuplesinanyof5!=120ways.Also,thecolumnscanbeorderedinanyof4!=24ways.Thus,thenumberofpresentationsis120*24=2880Exercise2.2.3cWecanorderthethreetuplesinanyofm!ways.Also,thecolum
