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AnOracleWhitePaperUpdatedNovember2009BestPracticesforConflictDetectionandResolutioninActive-ActiveDatabaseConfigurationsUsingOracleGoldenGateBestPracticesforConflictDetectionandResolutioninActive-ActiveDatabaseConfigurationsUsingOracleGoldenGateExecutiveOverview.............................................................................1Introduction.........................................................................................1KeyRequirementsforActive-ActiveConfigurations...........................33344458991113131516171717182021Real-Time,Low-ImpactDataMovement.........................................ConflictDetectionandResolution...................................................HeterogeneousEnvironmentSupport.............................................ConflictDetection................................................................................UnderstandingConflictsandComplexResolutions........................SimpleConflictResolutionMethodologies......................................HybridMethodologiesforConflictDetection...................................ComplexConflictResolution...............................................................QuantitativeResolution...................................................................TransactionConsistency...............................................................ConflictNotificationandTracking......................................................Exceptions.....................................................................................ResolutionNotification..................................................................MinimizingConflicts..........................................................................ApplicationSegregation................................................................PrimaryKeyGeneration................................................................ConflictAvoidance........................................................................OracleGoldenGateforActive-ActiveDatabases..............................OracleGoldenGateDataDefinitionLanguageReplication...........Conclusion........................................................................................BestPracticesforConflictDetectionandResolutioninActive-ActiveDatabaseConfigurationsUsingOracleGoldenGateExecutiveOverviewOneofthemosteffectivewaystoenableincreasedavailabilityandperformancefordatabaseinfrastructuresistoestablishanactive-activeenvironment,whichdistributesdatabasetransactionsacrossmultipledatabases.Beyonddisasterrecoveryandtolerance,active-activeconfigurationsfacilitatecontinuousoperations,offeradditionalrawcomputingcapacity,andprovidetheflexibilitytooptimizeworkloadmanagement.However,implementinganactive-activesolutionisnottrivial.Thekeytosuccessliesinreal-timedatamovement,conflictdetectionandresolution,andsupportforheterogeneousenvironments.Ofthethree,conflictdetectionandresolutionintroducesthemostcomplexity.ThiswhitepaperprovidesbestpracticesforconflictdetectionandresolutionandhighlightshowOracleGoldenGateaddressesthesechallenges.IntroductionAkeyobjectiveforanyITorganizationistocreatesoftwareapplicationsandadatabaseinfrastructurethatcanscaletomeetgrowingandchangingbusinessneeds.Withbusinessprocessesincreasinglymigratingtodigitaltransactions,thereisagrowingorganizationalrelianceanddependenceontheITgroup’sabilitytohandlelargervolumesofdataandusers,withlesssystemdowntime.Active-activeconfigurationsprovidesignificantperformanceandscalabilitybenefits;deliverexceptionalhigh-availability;andenablecontinuousoperationsfornotonlyunplannedinterruptionsbutalsoplannedoutagessuchasmigrations,upgrades,andsystemsmaintenance.Inmostcases,active-activeconfigurationsareconsideredtobepartofacontinuousavailability—notadisasterrecovery—plan.Atthehighendoftraditionaldisasterrecoveryplans,therearesolutionsthatofferanactive-passiveconfigurationwheretheactivesystemassumesalltheworkload,butwhenitfails,thepassivesystembecomesactiveandassumesthefullworkload.Undernormaloperatingconditions,thesecondary1BestPracticesforConflictDetectionandResolutioninActive-ActiveDatabaseConfigurationsUsingOracleGoldenGate2(passive)systemdoesn’tcontributetohandlingthedataprocessingload;itistwicetheinvestmenttoprovidethesameamountofprocessingpowerasasinglesystem.Bycomparison,anactive-activeconfigurationnotonlyfacilitatesveryhighlevelsofrecoverypointandrecoverytimeobjectives,butitalsoreturnsvalueontheinvestmentbyaddingcapacity,flexibility,andhigherperformancetotheoperationaldatainfrastructure.Implementinganeffectiveactive-activeconfigurationrequiresathoroughconsiderationoftechnologiesavailableforenablingthedatamovementandsharingbetweenthedatabaseinstances.Beforemovingforward,anorganizationmustunderstandthedifferentusecasesforactive-activeconfigurationsandthechallengesandbenefitsofeachconfiguration.Theymustalsounderstandthedifferentmethodsfordetectingdataconflictsthatoccurandhowtoeffectivelyresolvethoseconflicts.BestPracticesforConflictDetectionandResolutioninActive-ActiveDatabaseConf