1 / 8

SAP HANA Interview Questions

SAP HANA is a mammoth module

bestonlinetrainers
Download Presentation

SAP HANA Interview Questions

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. SAPHANAINTERVIEWQUESTIONS 1.Statethedifferenttypesofreplicationtechniques? Thethreetypesareasbelow: ETLbasedreplicationusingBODS TriggerbasedreplicationusingSLT ExtractorbaseddataacquisitionusingDXC 2. WhatisSLT? ThefullformofSLTisSAPLandscapeTransformationwhichisnothingbutatriggerbasedreplication.It isthereplicationtechnologytopassthedatafromthesourcesystemtothetargetsystem.Herethesource canbe eitherSAPornon-SAPwhereastheTargetsystemisSAPHANAsystemwhichcontainsHANA database. 3.Canweloadandreplicatedatafromonesourcesystemto multipletargetdatabase schemasofHANAsystem? Yes.Itcanbeloadedandreplicatedforupto4. 4.Canthetypeofdataloadandreplicationbespecified? Itcanbe eitherinrealtime,orscheduledby timeorbyinterval. 5.DefineConfigurationinSLT? Theinformationrequiredtocreatetheconnectionbetweenthesourcesystem,SLTsystem,andtheSAP HANAsystemisspecifiedwithintheSLTsystemasaConfiguration.AnewconfigurationinConfiguration &MonitoringDashboard(transactionLTR)canhencebedefined. 6.Isthereanyneedofpre-requisitebeforecreatingtheconfigurationandreplication? DMISadd-onisinstalledinSLTreplicationserverforSAPsourcesystems.Therole IUUC_REPL_REMOTEisassignedtotheuserforRFCconnectionbutnotDDIC.DMISadd-onisnot requiredandgrantsadatabaseusersufficientauthorizationfordatareplicationforanon-SAPsource system. 7.DefinewhatisConfigurationandMonitoringDashboard? TheyareapplicationsthatrunonSLTreplicationservertospecifyconfigurationinformation(suchas sourcesystem,targetsystem,andrelevantconnections)sothatdatacanbe replicated.Thereplication status(transactionLTR)canalsobe monitored. StatusYellowoccursduetotriggerswhicharenotyetcreatedsuccessfully. StatusRedoccursifmasterjobisaborted(manuallyintransactionSM37). 8. Whatisadvancedreplicationsettings? AdvancedReplicationsettingsisatransactionthatrunsonSLTreplicationservertospecifyadvanced 1 www.bestonlinetrainers.com SAPHANAINTERVIEWQUESTIONS

  2. replicationsettingslikemodifyingtargettablestructures,specifyingperformanceoptimizationsettingsreplicationsettingslikemodifyingtargettablestructures,specifyingperformanceoptimizationsettings thatdefinestransformationrules. 9DefineLatency? Latencyisthelengthoftimetoreplicatedata(atableentry)fromthesourcesystemtothetargetsystem. 10.Whatisloggingtable? Aloggingtableinthesourcesystemthatcanrecordanychangestoatablethatisbeingreplicated.This therebyensuresthatSLTreplicationservercanreplicatethesechangestothetargetsystem. 11.WhatareTransformationrules? TransformationruleisarulespecifiedintheAdvancedReplicationsettingstransactionforsourcetables suchawaythatthedataistransformedduringthereplicationprocess.Forexampleonecanspecifyruleto Convertfields,FillemptyfieldsandSkiprecords 12.Whena newconfigurationissetupwhathappens? ThedatabaseconnectionisautomaticallycreatedalongwithGUIDandMasstransferid(MT_ID). ConfigurationswiththesameschemanamecanbecreatedwhichisensuredbyschemaGUID. ThenamingofSLTjobsandthesystemcanuniquelyidentifyaschemawheretheMasstransferIDis used. 13.Whatarethefactorsthatinfluencethechange/increasethenumberofjobs? Thefactorsthatinfluencethechangeor increaseinthenumberofjobsarenumberofconfigurations managedbytheSLTreplicationserver,numberoftablestobeloaded/replicatedforeachconfiguration, expectedspeedofinitialload,expectedreplicationlatencytime. Asathumbrule,oneBDGjobshouldbe usedforeach10tablesinreplicationtoachieveacceptablelatencytimes. 14.WhenisthenumberofDataTransferjobschanged? ThenumberofdataTransferjobschangeswhenthespeedoftheinitialload/replicationlatencytimeis notsatisfactory,ifSLTreplicationserverhas moreresourcesthanthatisinitiallyavailable.Thenumberof initialloadjobsmaybe reducedafterthecompletionoftheinitialload 15.Mentionthejobsinvolvedinreplicationprocess? Themainjobsinvolvedinthereplicationprocessarestatedasbelow: MasterJob(IUUC_MONITOR_<MT_ID>) MasterControllingJob(IUUC_REPLIC_CNTR_<MT_ID>) Data LoadJob(DTL_MT_DATA_LOAD_<MT_ID>_<2digits>) Migration ObjectDefinitionJob(IUUC_DEF_MIG_OBJ_<2digits>) AccessPlanCalculationJob(ACC_PLAN_CALC_<MT_ID>_<2digits>) 16.Statetherelationbetweenthenumberofdatatransferjobsintheconfiguration settingsandtheavailableBGDworkprocesses? InSLTreplicationservereachjoboccupies1BGDworkprocessesandforeachconfiguration,the parameterDataTransferJobswouldrestrictthemaximumnumberofdataloadjobforeachmass 2 www.bestonlinetrainers.com SAPHANAINTERVIEWQUESTIONS

  3. transferID(MT_ID). Atleast4backgroundjobsarerequiredforamasstransferIDrequirestobeavailable.TheyareOne masterjob,Onemastercontrollerjob,Atleastonedataloadjob,Oneadditionaljobeitherfor migration/accessplancalculation/tochangeconfigurationsettingsin“ConfigurationandMonitoring Dashboard”. 17.Iftheparametersetfor“datatransferjobs”to04inaconfiguration“SCHEMA1”,a masstransferID001isassigned.Insucha casewhatjobsshouldbeinthesystem? Thejobsshouldbe1Masterjob(IUUC_MONITOR_SCHEMA1),1MasterControllerjob (IUUC_REPL_CNTR_001_0001)andatmost4paralleljobsforMT_ID001 (DTL_MT_DATA_LOAD_001_01/~02/~03/~04) Ifatthesametimelotsoftablesareselectedforload/replication,therecouldbe achancethatthereare notenoughbackgroundjobsavailabletostarttheload procedureforalltablesimmediately.Insuchacase thenumberofinitialloadjobscanbeincreased,orelsetableswillbehandledsequentially. Fortableswithlargevolumeofdatathetransaction“AdvancedReplicationSettings (IUUC_REPL_CONT)”tofurtheroptimizetheloadandreplicationprocedurefordedicatedtablescanbe used. 18.AftertheSLTreplicationisoverwhathappens? Afterthereplicationisover,theSLTreplicationservercreates1user,4roles,2storedproceduresand8 tablesasmentionedbelow: 1User 1Privilege 4Roles <REPLICATIONSCHEMA>_DATA_PROV <REPLICATION_SCHEMA>_POWER_USER <REPLICATION_SCHEMA>_USER_ADMIN <REPLICATION_SCHEMA>_SELECT 2Storedprocedures RS_GRANT_ACCESS,RS_REVOKE_ACCESS 8Tables DD02L,DD02T,RS_LOG_FILES,RS_MESSAGES,RS_ORDER,RS_ORDER_EXT, RS_SCHEMA_MAP,RS_STATUS 19.Statethedifferentreplicationscenarios? ThedifferentreplicationscenariosareLoad,Replicate,Stop,SuspendandResume. Beforeanyapplicationtableisselected,theinitialloadofthetablesDD02L,DD02T&DD08Lmustbe completedastheycontainthemetadatainformation. Load:Thisstartsaninitialloadofreplicationdatafromthesourcesystem.Thecompleteprocedureisa one-timeevent.Oncecompleted,furtherchangestothesourcesystemdatabasewillnotbereplicated. Alsofortheinitialloadprocedure,neitherdatabasetriggersnorloggingtablesarecreatedinthesource system.Thedefaultsettingsusereadingtype3(DB_SETGET)withupto3backgroundjobsinparallelto loadtablesinparallelorsubsequentlyintotheHANAsystem. Replicate:Thiscombinesaninitialloadprocedureandthesubsequentreplicationprocedure(realtimeor 3 www.bestonlinetrainers.com SAPHANAINTERVIEWQUESTIONS

  4. scheduled). Beforethestartofinitialloadprocedure,triggerofdatabaseandrelatedloggingtablearecreatedforeach tableinthesourcesystemaswellasinSLTreplicationserver. StopReplication:Thisstopsanycurrentloadorreplicationprocessofatable. Thestopfunctionremovesthedatabasetriggerandrelated loggingtablescompletely.Thisfunctionis usedonlyifyouwanttocontinueaselectedtableotherwiseitmustbeinitiallyloadedagaintoensuredata consistency. Suspend:Thispausesatablefromarunningreplication.Alsothedatabasetriggerwillnotbedeletedfrom thesourcesystem.Therecordingofchangeswouldcontinueandtherelatedinformationwouldbestored intherelatedloggingtablesinthesourcesystem. Iftablesaresuspendedforalongtimethesizeofloggingtablesmayincreaseandadjustthetablespaceif required. Resume:Thisrestartstheapplicationforasuspendedtable.Theprevioussuspendedreplicationwillbe resumed(nonewinitialloadrequired). 20.IfthereplicationissuspendedforalongperiodoftimeorsystemoutageofSLTor HANAsystemwhatwouldhappen? Thesizeoftheloggingtablesincreases. 21.Howcanunnecessarylogginginformationfrombeingstoredbeavoided? Unnecessarylogginginformationstoragecanbeavoidedby pausingthereplicationwhichisbystopping theschema-relatedjobs. 22.ArethetablesizeinSAPHANAdatabaseandin thesourcesystemthesame? NotheyarenotsameasHANAdatabasesupportscompression. 23.Whenistablepartitioningopted? IfthetablesizeinHANAdatabaseexceeds2 billionrecords,thetableshouldbesplittedbyusing portioningfeaturesbyusing“Advancedreplicationsettings”(transactionIUUC_REPL_CONT,tabpage IUUC_REPL_TABSTG). 24.Wherearetransformationrulesdefined? Transformationrulesaredefinedbyusing“Advancedreplicationsettings”(transaction IUUC_REPL_CONT,tabpageIUUCASSRULEMAP) 25.Ifthesourcesystemisnon-SAPsystem,arethereanyspecialconsiderations? Thetrigger-basedreplicationconceptisactuallymeantforSAPsourcesystems.Themaindifferencesare asbelow: a)Therewouldbea databaseconnectionbetweennon-SAPsourceandSLTsysteminsteadofRFC. b)Sourcemusthaveprimarykey c)TablesDD02L,DD02Twhichcontainsmetadataarejustinitiallyloadedbutnot replicated. d)ThereadmodulesresidesonSLTsystem. e)Tableswithdatabasespecificformatsmayneedtransformationrulesjustbeforetheyarereplicated. 4 www.bestonlinetrainers.com SAPHANAINTERVIEWQUESTIONS

  5. f)OnlySAPsupporteddatabases(withrespectiveDBSLforSAPNetWeaver7.02)aresupportedasnon-f)OnlySAPsupporteddatabases(withrespectiveDBSLforSAPNetWeaver7.02)aresupportedasnon- SAPsourcesystems. 26.Statethepotentialissuesin thecreationofaconfiguration? Themostpotentialissuesintheconfigurationcreationisthemissingadd-onDMIS_2010insource system,missingtheproperroleofSAP_IUUC_REPL_REMOTEforRFCuser (SAP_IUUC_USERforSLTsystem)andiftheLogoncredentialsarenotcorrect 27.HowisitensuredthatdataisconsistentinsourcesystemandHANAsystem? Sinceanychangesinthesourcesystemthatoccursistrackedinthededicatedloggingtables,the replicationstatusforeachchangeddatarecordwillbetransparent.Anentryofloggingtableisdeleted afteraneverysuccessfulcommitstatementfromHANAdatabaseandthisprocedureensuresthedata consistencybetweensourcesystemandHANAsystem. 28.DoesSLTforSAPHANAsupportdatacompressionlikeSAPHANAdatabase? YesSLTforSAPHANAsupportsdatacompressionlikeSAPHANAdatabaseandthisisautomatically coveredbythe RFCconnectionusedfordatareplicationfromtheSAPsour. 29.WhataretheproductnamesinSAPHANA? Inshortanswerit'samystery.AlotofchangeshavehappenedaroundSAPandnowit’scalledSAPHANA Appliance,SAPHANADatabaseandSAPHANAStudio.AllapplicationsbuiltonHANAwillbe marked "poweredbySAPHANA".Andthisisprobablytobechangedagain. 30.WhatisSAPHANAAppliance1.0? SAPHANA1.0isananalyticsappliancewhichconsistsofcertifiedhardware,andInMemoryDataBase (IMDB),anAnalyticsEngineandsometoolingforgettingdatainandoutofHANA.Thelogicand structuresarebuiltbytheuserandatoolisusede.g.SAPBusinessObjects,tovisualizeoranalyzedata. 31.StatethelimitationsofHANA1.0? Thelimitationsareveryless.Itcanonlyreplicatecertaindatafromcertaindatabasesandincertain formatsusingtheSybaseReplicationServer.TheBatchloadingisdoneusingSAPBusinessObjectsData Services4.0andisoptimizedonlyforSAPBusinessObjectsBI4.0reporting. 32.WhatisSAPHANA1.5,1.2or1.0SP03? Theyareallthesamething,and1.0SP03istoutedtobethefinalnamewhichshouldgointoRampUp (beta)inQ42011.ThisallowsanySAPNetWeaverBW7.3DataWarehousetobe migratedintoaHANA appliance.HANA1.0SP03specificallyalsoacceleratesBWcalculationsandplanning,whichmeanseven moreperformancegainscanbeattained. 33.DifferentiatebetweenHANAandIMDB? HANAisthenameforthecurrentBIappliance(HANA1.0)andtheBWDataWarehouseappliance (HANA1.0SP03).BothusetheSAPIMDBDatabaseTechnology(SAPHANADatabase)astheir underlyingRDBMS.SAPcanbe expectedtostarttodifferentiatethismoreclearlyasitstartstoposition thetechnologyforusecasesotherthanAnalytics. 5 www.bestonlinetrainers.com SAPHANAINTERVIEWQUESTIONS

  6. 34.IfNetWeaverBWcanberunonIMDB/HANA,whycan'ttheBusinessSuite/ERP6.0be34.IfNetWeaverBWcanberunonIMDB/HANA,whycan'ttheBusinessSuite/ERP6.0be runtoo? Thisisbecauseit'snotmatureenoughtosupportbusinesscriticalapplications.Fromatechnology perspective,itisanywayspossibletorunthe BusinessSuiteonIMDBandSAPhastrialedmovingsome largedatabasesintoIMDBalready. 35.WhatisHANAexcellentat? Themostimportantthingtonoteis,HANAbringstothetableistheabilitytoaggregatelargedata volumesinnearreal-time-andtohavethedataupdatedinnearreal-time.Demosshowhundredsof billionsofrecordsofdatabeingaggregatedinamatterofseconds.HenceSAPhas builtasetofAnalytics AppsontopofHANAandthesearesettobegreatpointusecasestogetcustomersupandrunning quickly. 36.WhatisHANAnotgoodat? SomecurrentissueshavebeennoticesaroundHANAwhendeliveringad-hocanalytics,especiallywhen usingtheSAPBusinessObjectsWebitool.Nodoubtthattheproblemisthatonecanaskcomputationally verydifficultquestionswithWebi,whichcausesverylongresponsetimeswithHANA.SAPneedstobuild optimizationforbothWebiandHANAtoreducethecomputationalcomplexityofthesequestions. 37.WhatisthecostofHANA? ThelicensingcostofHANAisnotconfirmedbSAPbut thehardwareissomewherearound$1-200kper TB.Inadditiontotheselicensingcoststhisisstillbeingmadeonaper-customerbasis. 38.WhatisthereasonforthespeedofHANA? Theinformationcanbe retrievedfromRegularRDBMStechnologiesputtheinformationonspinning platesofiron(harddisks).Theinformationisstoredinelectronicmemory,whichissome50xfaster (dependingonhowyoucalculate).Itstoresacopyonmagneticdisk,incaseofpowerfailureorthelike. Alsotoaddin,mostSAPsystemshavethedatabaseononesystemandacalculationengineonanother, andtheinformationispassedbetweenthem.WithHANA,thisall happenswithinthesamemachine. 39.IsOraclereplacedbyHANA/IMDB? Oncethe BusinessSuiterunsonIMDB,OraclewillnotbeneededformanymorebySAPcustomerswho purchaseHANA.Theshorttermisnotaffectedbecauseevenif HANAisboughttodayitstillneedsan OracleERPsystem. 40.Statethe10:1compressionwithHANAwhencomparedtoOracle? Whena typicaluncompressedOracleorMicrosoftSQLServerdatabaseisputintoHANA,itwillbe10x smallerthanbeforeandthisisbecauseofthewaythatHANAstoresinformationinacompressed format.Mostdatabasesarenowcompressedandthesenumbersmaynotfiteveryscenario,andtoaddto this2x the RAMasyourdatabaseisneededincludingaplusroomforgrowth.SizingofHANAisstilla darkart. 6 www.bestonlinetrainers.com SAPHANAINTERVIEWQUESTIONS

  7. 41.Whatismeantby“buyaHANAonly2.5xsmallerthanmybigOracleRDBMS”?How41.Whatismeantby“buyaHANAonly2.5xsmallerthanmybigOracleRDBMS”?How aboutarchivinganddataageing? InsomeinstancesHANAappliancethatisonly2.5xsmallerthanitwouldbeunderOracleandonlythis canbe bought.Dataageingisnotapartofthe1.0release,butSAPiscertainlyworkingonit. 42.What'stheextendedmarketopportunityforIMDB? Afewanalystsseemtohavetappedonthatthewidermarketopportunitywhichisbelievedtobe huge. NotonlySAPapplicationsbutanythirdpartythatrequiresultra-highspeed.It’s notjustanappliancebut adevelopmentplatform. 43.WhathardwareissupportedinSAPHANArightnow? Allofthemajorvendorse.g.HP,IBM,Dell,areofferingHANAnow.TechnicallyHANAwillrunonany Intelx64basedsystemfromyourlaptopthroughtothebig40-core,2TBRAMservers.Itishoweveronly supportedonasmallnumberofbigrack-mountserversliketheDellR910andHPDL980. 44.DoesHANArunonblades?Ifnotwhy? It'sstillnotclearbut probablybecausethe bladesdoesn’tyetofferthesameperformance.HANAis optimizedfortheIntelX7560CPUandrunsfastestonthis.Forinstance,theDellM910bladecanonly run2xX7650CPUsand512GbRAMinthisconfiguration,whichprobablyexplainsthelimitations.One thingissurethatHANAwilleventuallyrunonbladesasit'sborntorunonbladetechnology. 45.CANSAPmaketheirownIMDB/HANAhardware? Itcanbutonly inthelabssofar.NosuchpublicplanstocompeteagainstIBM/HP/Dellisthereinthis space,butitcouldmakesenseforSAPtoentertheappliancemarket,especiallyinthecontextofData CentersandevenmoresointhecontextoftheSAPBusinessbyDesigncloudoffering,whichwillrunon IMDB. 46.HowbigdoesHANAscale? Theorywiseatleastverywell.Mostmid-sizeworkloads-2TBofin-memorystorageisequivalentto5- 20TBofOraclestoragecanberunbythe biggestsingleserverHANAhardware.HANAworksinaway thatmeansitispossibletochainmultiplesystemstogetherwhichmeansthatscalabilityhasthus-farbeen determinedbythesizeofcustomers'wallets.WhilstSAPtalkup"BigData"quitealot,HANAcurrently onlyscalestothesmall-endofBigDatareferringtothe kindofhugedatasetsthatFaceBookor Google havetostore-notTerabytes,butratherPetabytes. 47.HANAuseswhichstoragesubsystem? Asharednetworkattachedandvariesfromvendortovendorandiscalledthestorage.Herebothregular magneticdisksandSSDstoragecanbeusedforthebackupofthedatabase(HANArunsinmemory remember,sodiskstorageisjustforbackup,andlater,fordataageing).Iftheoperatorrequire2xstorage thatyouhaveRAM,whichis2xthedatabasesize-i.e.storagesize=4xdatabasesize.Anywaysinmost casesthereisadditionalultra-highspeedSSDstorageforlogfiles. 48.HANAsupportinreal-timewhattypesofsourcedatabase? IfSybaseReplicationServer(SRS)fornearreal-timedataisusedthenthelicensingstill(SAPhavelicense 7 www.bestonlinetrainers.com SAPHANAINTERVIEWQUESTIONS

  8. dealspending)needstochecked.IfDB2isrunthenits finebutwithOracleandMicrosoftSQLServer therearesomelicensechallenges.SoiflicenseisboughtthroughSAP,becauseyoumayhavealimited licensethatdoesnotallowextraction. 49.ForbatchloadswhatsourcedatabasesdoesHANAsupport? IfSAPBusinessObjectsDataServices4.0 isusedforbulkloadsthenitwouldbethebest.BO-DSisavery flexibleExtract,Transform&Loadtoolthatcansupportmanydatabases 50.WhatadditionallimitationsdoesSybaseReplicationServerpresent? SRShasadditionalrestrictionswhichareworthtobeunderstood.ItonlyreplicatesUnicodedataand doesnotsupportIBMDB2compresstables. WanttoLEARNSAPHANA? GettrainedbySAPHANAexperts.KnowaboutSAPHANATraining course http://www.bestonlinetrainers.com/bigdata/sap-hana-training.html REGISTERFORFREEDEMOTODAY http://www.bestonlinetrainers.com/demo/index.html Trustedby1000+ trainees info@bestonlinetrainers.com USA:+(1)6783896789|UK:+(44)-2032393637|India:+(91)9246449191 8 www.bestonlinetrainers.com SAPHANAINTERVIEWQUESTIONS

More Related