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1、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:
2、(Robbie,Banks,901-222,12345),(Lena,Hand,805-333,12345),(Lena,Hand,805-333,23456)Exercise2.2.1cForrelationAccountsandthefirsttuple,thecomponentsare:123456àacctNosavingsàtype12000àbalanceForrelationCustomersandthefirsttuple,thecomponentsare:RobbieàfirstNameBanksàlastName901-222àidNo1
3、2345àaccountExercise2.2.1dForrelationAccounts,arelationschemais:Accounts(acctNo,type,balance)ForrelationCustomers,arelationschemais:Customers(firstName,lastName,idNo,account)Exercise2.2.1eAnexampledatabaseschemais:Accounts(acctNo,type,balance)Customers(firstName,lastName,idNo,accou
4、nt)Exercise2.2.1fAsuitabledomainforeachattribute:acctNoàIntegertypeàStringbalanceàIntegerfirstNameàStringlastNameàStringidNoàString(becausethereisahyphenwecannotuseInteger)accountàIntegerExercise2.2.1gAnotherequivalentwaytopresenttheAccountrelation:acctNobalancetype3456725savings23
5、4561000checking1234512000savingsAnotherequivalentwaytopresenttheCustomersrelation:idNofirstNamelastNameaccount805-333LenaHand23456805-333LenaHand12345901-222RobbieBanks12345Exercise2.2.2Examplesofattributesthatarecreatedforprimarilyservingaskeysinarelation:UniversalProductCode(UPC)
6、usedwidelyinUnitedStatesandCanadatotrackproductsinstores.SerialNumbersonawidevarietyofproductstoallowthemanufacturertoindividuallytrackeachproduct.VehicleIdentificationNumbers(VIN),auniqueserialnumberusedbytheautomotiveindustrytoidentifyvehicles.Exercise2.2.3aWecanorderthethreetupl
7、esinanyof3!=6ways.Also,thecolumnscanbeorderedinanyof3!=6ways.Thus,thenumberofpresentationsis6*6=36.Exercise2.2.3bWecanorderthethreetuplesinanyof5!=120ways.Also,thecolumnscanbeorderedinanyof4!=24ways.Thus,thenumberofpresentationsis120*24=2880Exercise2.2.3cWecanorderthethreetuplesina
8、nyofm!ways.Also,thecolumns
