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DESIGNINGADATABASEAPPLICATIONINVB60ABSTRACTBEFOREYOUSTARTTODESIGNADATABASE,IT’SIMPORTANTYOUUNDERSTANDEXACTLYWHATADATABASEISANDWHATTYPESOFDATABASESYOUHAVETOCHOOSEFROMTHEAPPLICATIONTYPEWILLAFFECTTHEDATABASETYPETHATYOUCHOOSEWHATISADATABASEADATABASEISREALLYASYSTEMTHATCONTAINSMANYDIFFERENTOBJECTSUSEDTOGETHERTOALLOWYOURAPPLICATIONFASTANDEFFICIENTACCESSTOTHEDATAYOUCANUSEMANYEXAMPLESOFDATABASESWITHYOURAPPLICATIONTHEMOSTCOMMONOFTHESEAREASFOLLOWSMICROSOFTACCESS；MICROSOFTFOXPRO；ORACLEPERSONALEDITION7IOR8I；ANDMSSQLSERVER700ISONLYAFEWTOMENTIONALLTHESEDATABASESCANRUNONASTANDALONECOMPUTERANDALLOWYOUTOCREATEVERYCOMPLEXDATABASESFORYOURAPPLICATIONSPICKINGTHERIGHTDATABASEFORYOURAPPLICATIONISEXTREMELYIMPORTANT,BECAUSETHEWRONGONEWILLAFFECTPERFORMANCEANDMAKEYOURJOBASADEVELOPERSOMUCHMOREDIFFICULTBEFORESTARTINGTHEDESIGNPROCESS,YOUNEEDTOSELECTADATABASEWHENWORKINGWITHVISUALBASIC,THEDATABASETHATYOUCANCHOOSEFROMFALLINTOTWODISTINCTGROUPSLOCALDATABASESCANBEACCESSEDDIRECTLYFROMVISUALBASICTHROUGHVISUALBASIC’SDATABASEJETENGINE；ANDREMOTEDATABASESCANNOTBEACCESSEDBYUSINGVISUALBASIC’SSTANDARDDATABASEACCESSCAPABILITIESUNDERSTANDINGTHEDIFFERENCESWILLHELPYOUSELECTTHECORRECTDATABASEFORYOURAPPLICATIONHOWEVER,INVISUALBASIC6,THEREISNOWAWAYTOACCESSBOTHLOCALANDREMOTEDATABASESUSINGTHESAMEDATABASEACCESSCONTROLSANDOBJECTSKNOWNASTHEACTIVEXDATAOBJECTSUNDERSTANDINGUNIVERSALDATAACCESSUDAASDATABASESHAVEGROWNANDMOVEDOFFTHELOCALCOMPUTERANDONTONETWORKEDDATABASESERVERS,THEMETHODSEMPLOYEDTOACCESSTHEDATABASESHAVECHANGEDMICROSOFTHASADDRESSEDTHESECHANGESBYDEVELOPINGSTRATEGYTOALLOWFORANYCOMPANYORDATABASETOBEACCESSEDTHESAMEWAYTHISISCALLEDUNIVERSALDATAACCESS,ORUDAUNDERSTANDINGWHATUDAMEANSISNOTASSIMPLEASUNDERSTANDINGTOUSEITTHEREASONFORTHISISTHATUDAISASETOFRULESANDACCESSMETHODSTHATMUSTBEFOLLOWEDBYANYCOMPANYTHATISCREATINGADATABASEACCESSMETHODTOBEUSEDTHISALLOWSYOU,THEPROGRAMMER,TOACCESSANYDATABASETHESAMEWAYBUTWHATISUDAUNIVERSALDATAACCESSISAPLATFORM,APPLICATIONSANDTOOLSCONCEPTTHATMICROSOFTHASDEVELOPEDTHATDEFINESANDDELIVERSTHESTANDARDSFORALLFUTUREAPPLICATIONDEVELOPMENTUSINGUDASTANDARDSWILLPROVIDEHIGHPERFORMANCEACCESSTOMANYTYPESOFDATAANDINFORMATIONTHATRESIDEONMULTIPLEPLATFORMS,ANDAPROGRAMMINGINTERFACETHATWILLWORKWITHALMOSTANYTOOLORLANGUAGEUSINGTHESKILLSTHATDEVELOPERSALREADYHAVETHISISACCOMPLISHEDBYUSINGMICROSOFT’SDATAACCESSCOMPONENTSMDAC,ASWELLASANINTEGRATEDSETOFTECHNOLOGIES,WHICHINCLUDEACTIVEXDATACOMPONENTSADO,OLEDB,ANDOPENDATABASECONNECTIVITYODBCTHEBENEFITSOFUSINGTHESESTANDARDSINCLUDETHEFOLLOWINGHIGHPERFORMANCEACCESSTODATA–PROVIDESTHEABILITYTOSCALEANYAPPLICATIONORCOMPONENTTOSUPPORTCONCURRENTLYCONNECTEDUSERSWITHOUTLOSINGPERFORMANCE；RELIABILITY–REDUCESTHENUMBEROFCOMPONENTSTOSUPPORTONTHECLIENTPC；ANDWIDEINDUSTRYSUPPORT–MANYVENDORSINCLUDINGMICROSOFTHAVEALREADYANNOUNCEDSUPPORTFORTHEUDASTANDARDSINPREVIOUSRELEASESOFVISUALBASIC,YOUNEEDEDTOCHOOSEFROMEITHERDAOLOCALACCESSMETHODSTODATAORRDOREMOTEACCESSTODATANOW,WITHTHESUPPORTOFUDA,VISUALBASICHASATHIRDMETHODFORDATAACCESSCALLEDADO,ORACTIVEXDATAOBJECTSTHISALLOWSYOUTOCOMBINETHEDIFFERENTWAYSOFACCESSINGDATAINTOONESETOFPROGRAMMINGCALLSANDOBJECTSADOWORKSINCONJUNCTIONWITHOLEDBANDODBCTOPROVIDEACCESSTOONEDATABASEYOUMIGHTBEWORKINGWITHGETTINGFORWARD,MICROSOFTPLANSTOPHASEOUTODBCINFAVOUROFOLEDBANDTHEUDASTANDARDSHOWEVER,FORTHENEARFUTURE,DAOANDRDO,ASWELLASODBC,WILLSTILLBESUPPORTEDTOALLOWDEVELOPERSTOSLOWLYMOVEUPTOTHENEWSTANDARDSOFDATAACCESSLOCALDATABASESLOCALDATABASESAREGENERALLYMUCHSMALLERTHANTHEREMOTETYPEOFDATABASETHEFOLLOWINGDATABASESFALLINTOTHISCATEGORYMICROSOFTACCESS；MICROSOFTFOXPRO；LOTUSWORKSHEETS；MICROSOFTEXCELWORKSHEETS；DBASE；PARADOX；ANDASCIIASYOUCANSEE,THESEPCRESIDENTDATABASETYPESHAVEBEENAROUNDFORAWHILEANDAREAVAILABLEFROMALMOSTANYCOMPUTERSOFTWARESTOREACCESSINGTHESEDATABASESDOESN’TREQUIREANYOTHERSOFTWARETOBEINSTALLEDONTHEPC,NORDOESITREQUIRESPECIALKNOWLEDGEONHOWTOWORKWITHTHEMHOWEVER,THESIZEOFLOCALDATABASESISRESTRICTEDMICROSOFTACCESS97DATABASESCAN’TEXCEED1GBGIGABYTELOCALDATABASESAREGENERALLYUSEDFORSINGLEUSERAPPLICATIONSSUCHASCHECKBOOKS,ADDRESSBOOKS,ANDPERSONALINFORMATIONMANAGERSSOMEENTERPRISINGTEENAGERSHAVECREATEDDATABASEAPPLICATIONSTHATHELPTHEMKEEPTRACKOFBASEBALLCARDSORVIDEOTAPESSOINDECIDINGWHATYOURAPPLICATIONWILLADDRESSANDHOWITWILLBEUSEDACTUALLYHELPSYOUINTHEDATABASESELECTIONPROCESSREMOTEDATABASESBYDEFINITIONREMOTEDATABASESDON’TRESIDEONTHEUSER’SPC,BUTTHISISNOTALWAYSTRUEINFACT,AREMOTEDATABASEISANYTYPEOFDATABASETHATREQUIRESANODBCOPENDATABASECONNECTIVITYDRIVERFORANAPPLICATIONTOACCESSITODBCDATABASESFALLINTOTWOMAINCATEGORIESONETHATRUNONASINGLEPCANDTHELARGERCORPORATEONESTHATREQUIRELARGE,VERYPOWERFULCOMPUTERSCALLEDSERVERSWITHLARGEAMOUNTSOFAVAILABLEDISKSPACEDATABASESERVERSAREUSEDTOSEPARATETHEWORKLOADBETWEENTHECLIENTPCWHERETHEAPPLICATIONEXECUTESANDTHEDATABASESYSTEMWHERETHEDATABASEQUERIESAREPERFORMEDTHISPROVIDESTHEAPPLICATIONWITHFASTDATAACCESSWITHOUTSLOWINGDOWNTHEUSERSPCMOSTTHELARGESERVERTYPEDATABASESPROVIDEVERSIONSTHATWILLRUNONSTANDALONEPCSMOSTLARGECORPORATIONSUSEONEOFTHEFOLLOWINGDATABASESYSTEMSTHOUGHTHISISNOTTOSAYTHATOTHERSAREN’TOUTTHEREORACLE；SYBASE；ANDMICR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