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Excel®PowerPivot&PowerQueryForDummies®
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Excel®PowerPivot&PowerQueryFor
Dummies®

Visit
www.dummies.com/cheatsheet/excelpowerpivotpowerquery
toviewthisbook’scheatsheet.
TableofContents
Cover
Introduction
AboutThisBook
FoolishAssumptions
HowThisBookIsOrganized
IconsUsedInThisBook
BeyondtheBook
WheretoGofromHere

PartI:SuperchargedReportingwithPowerPivot
Chapter1:ThinkingLikeaDatabase
ExploringtheLimitsofExcelandHowDatabasesHelp
GettingtoKnowDatabaseTerminology
UnderstandingRelationships

Chapter2:IntroducingPowerPivot
UnderstandingthePowerPivotInternalDataModel
ActivatingthePowerPivotAdd-In
LinkingExcelTablestoPowerPivot

Chapter3:ThePivotalPivotTable
IntroducingthePivotTable
DefiningtheFourAreasofaPivotTable
CreatingYourFirstPivotTable
CustomizingPivotTableReports
UnderstandingSlicers

CreatingaStandardSlicer
GettingFancywithSlicerCustomizations
ControllingMultiplePivotTableswithOneSlicer
CreatingaTimelineSlicer

Chapter4:UsingExternalDatawithPowerPivot


LoadingDatafromRelationalDatabases
LoadingDatafromFlatFiles
LoadingDatafromOtherDataSources
RefreshingandManagingExternalDataConnections

Chapter5:WorkingDirectlywiththeInternalDataModel
DirectlyFeedingtheInternalDataModel
AddingaNewTabletotheInternalDataModel
RemovingaTablefromtheInternalDataModel
CreatingaNewPivotTableUsingtheInternalDataModel
FillingtheInternalDataModelwithMultipleExternalDataTables

Chapter6:AddingFormulastoPowerPivot
EnhancingPowerPivotDatawithCalculatedColumns
UtilizingDAXtoCreateCalculatedColumns
UnderstandingCalculatedMeasures
FreeYourDataWithCubeFunctions

Chapter7:PublishingPowerPivottoSharePoint
UnderstandingSharePoint
UnderstandingExcelServicesforSharePoint
PublishinganExcelWorkbooktoSharePoint

PublishingtoaPowerPivotGallery

PartII:WranglingDatawithPowerQuery
Chapter8:IntroducingPowerQuery
InstallingandActivatingaPowerQueryAdd-In
PowerQueryBasics
UnderstandingColumn-LevelActions
UnderstandingTableActions

Chapter9:PowerQueryConnectionTypes
ImportingDatafromFiles
ImportingDatafromDatabaseSystems
ManagingDataSourceSettings

Chapter10:TransformingYourWaytoBetterData
CompletingCommonTransformationTasks
CreatingCustomColumns
GroupingandAggregatingData

Chapter11:MakingQueriesWorkTogether
ReusingQuerySteps
UnderstandingtheAppendFeature
UnderstandingtheMergeFeature

Chapter12:ExtendingPowerQuerywithCustomFunctions


CreatingandUsingaBasicCustomFunction
CreatingaFunctiontoMergeDatafromMultipleExcelFiles
CreatingParameterQueries


PartIII:ThePartofTens
Chapter13:TenWaystoImprovePowerPivotPerformance
LimittheNumberofRowsandColumnsinYourDataModelTables
UseViewsInsteadofTables
AvoidMulti-LevelRelationships
LettheBack-EndDatabaseServersDotheCrunching
BewareofColumnswithNon-DistinctValues
LimittheNumberofSlicersinaReport
CreateSlicersOnlyonDimensionFields
DisabletheCross-FilterBehaviorforCertainSlicers
UseCalculatedMeasuresInsteadofCalculatedColumns
Upgradeto64-BitExcel

Chapter14:TenTipsforWorkingwithPowerQuery
GettingQuickInformationfromtheWorkbookQueriesPane
OrganizingQueriesinGroups
SelectingColumnsinQueriesFaster
RenamingQuerySteps
QuicklyCreatingReferenceTables
CopyingQueriestoSaveTime
SettingaDefaultLoadBehavior
PreventingAutomaticDataTypeChanges
DisablingPrivacySettingstoImprovePerformance
DisablingRelationshipDetection

AbouttheAuthor
CheatSheet
AdvertisementPage
ConnectwithDummies

EndUserLicenseAgreement


Introduction
Overthepastfewyears,theconceptofself-servicebusinessintelligence(BI)hastaken
overthecorporateworld.Self-serviceBIisaformofbusinessintelligenceinwhich
enduserscanindependentlygeneratetheirownreports,runtheirownqueries,and
conducttheirownanalyses,withouttheneedtoengagetheITdepartment.
Thedemandforself-serviceBIisadirectresultofseveralfactors:
Morepowerusers:Organizationsarerealizingthatnosingleenterprisereporting
systemorBItoolcanaccommodatealloftheirusers.Predefinedreportsandhighleveldashboardsmaybesufficientforcasualusers,butalargeportionoftoday’s
usersaresavvyenoughtobeconsideredpowerusers.Powerusershaveagreater
understandingofdataanalysisandprefertoperformtheirownanalysis,often
withinExcel.
Changinganalyticalneeds:Inthepast,businessintelligenceprimarilyconsisted
ofIT-manageddashboardsshowinghistoricdataonanagreed-uponsetofkey
performancemetrics.Managersnowdemandmoredynamicpredictiveanalysis,the
abilitytoperformdatadiscoveryiteratively,andthefreedomtotakethehardleft
andrightturnsondatapresentation.ThesemanagersoftenturntoExceltoprovide
theneededanalyticsandvisualizationtools.
SpeedofBI:UsersareincreasinglydissatisfiedwiththeinabilityofITtoquickly
delivernewreportingandmetrics.MosttraditionalBIimplementationsfail
specificallybecausetheneedforchangesandanswerstonewquestions
overwhelminglyoutpacestheITdepartment’sabilitytodeliverthem.Asaresult,
usersoftenfindwaystoworkaroundtheperceivedITbottleneckandultimately
buildtheirownshadowBI(undertheradar)solutionsinExcel.
Recognizingtheimportanceoftheself-serviceBIrevolutionandtheroleExcelplays
init,MicrosofthasmadesubstantialinvestmentsinmakingExcelthecornerstoneofits
self-serviceBIoffering.TheseinvestmentshaveappearedstartingwithExcel2007.
Hereareafewofnote:theabilitytohandleoveramillionrows,tighterintegrationto

SQLServer,pivottableslicers,andnotleastofall,theintroductionofthePowerPivot
andPowerQueryadd-ins.
WiththereleaseofExcel2016,MicrosofthasaggressivelymovedtomakeExcela
playerintheself-serviceBIarenabyembeddingbothPowerPivotandPowerQuery
directlyintoExcel.
Forthefirsttime,ExcelisanintegralpartoftheMicrosoftBIstack.Youcanintegrate
multipledatasources,definerelationshipsbetweendatasources,processanalysis
servicescubes,anddevelopinteractivedashboardsthatcanbesharedontheweb.
Indeed,thenewMicrosoftBItoolsblurthelinebetweenExcelanalysisandwhatis
traditionallyITenterprise-leveldatamanagementandreportingcapabilities.


WiththesenewtoolsintheExcelwheelhouse,it’sbecomingimportantforbusiness
analyststoexpandtheirskillsetstonewterritory,includingdatabasemanagement,
querydesign,dataintegration,multidimensionalreporting,andahostofotherskills.
Excelanalystshavetoexpandtheirskillsetknowledgebasefromtheone-dimensional
spreadsheetstorelationaldatabases,dataintegration,andmultidimensionalreporting,
That’swherethisbookcomesin.Here,you’reintroducedtothemysteriousworldof
PowerPivotandPowerQuery.Youfindouthowtoleveragetherichsetoftoolsand
reportingcapabilitiestosavetime,automatedataclean-up,andsubstantiallyenhance
yourdataanalysisandreportingcapabilities.


AboutThisBook
Thegoalofthisbookistogiveyouasolidoverviewoftheself-serviceBIfunctionality
offeredbyPowerPivotandPowerQuery.Eachchapterguidesyouthroughpractical
techniquesthatenableyouto
ExtractdatafromdatabasesandexternalfilesforuseinExcelreporting
Scrapeandimportdatafromtheweb
Buildautomatedprocessestocleanandtransformdata

Easilyslicedataintovariousviewsonthefly,gainingvisibilityfromdifferent
perspectives
Analyzelargeamountsofdataandreporttheminameaningfulway
Createpowerful,interactivereportingmechanismsanddashboards


FoolishAssumptions
Overthepastfewyears,Microsofthasadoptedanagilereleasecycle,allowingthe
companytoreleaseupdatestoMicrosoftOfficeandthepowerBItoolspractically
monthly.ThisisgreatnewsforthosewholoveseeingnewfeaturesaddedtoPower
PivotandPowerQuery.(It’snot-so-greatnewsifyou’retryingtodocumentthe
featuresofthesetoolsinabook.)
MyassumptionisthatMicrosoftwillcontinuetoaddnewbellsandwhistlestoPower
PivotandPowerQueryatarapidpaceafterpublicationofthisbook.Soyoumay
encounternewfunctionalitynotcoveredhere.
ThegoodnewsisthatbothPowerPivotandPowerQueryhavestabilizedandalready
haveabroadfeatureset.SoI’malsoassumingthatalthoughchangeswillbemadeto
thesetools,theywon’tbesodrasticastoturnthisbookintoadoorstop.Thecore
functionalitycoveredinthesechapterswillremainrelevant—evenifthemechanics
changeabit.


HowThisBookIsOrganized
Thechaptersinthisbookareorganizedintothreeparts.PartIfocusesonPowerPivot.
PartIIexploresPowerQuery.PartIIIwrapsupthebookwiththeclassicPartofTens.

PartI:SuperchargedReportingwithPowerPivot
PartIisallaboutgettingyoustartedwithPowerPivot.Chapters1and2startyouoff
withbasicPowerQueryfunctionalityandthefundamentalsofdatamanagement.
Chapter3providesanoverviewofpivottables—thecornerstoneofMicrosoftBI

analysisandpresentation.InChapters4and5,youdiscoverhowtodeveloppowerful
reportingwithexternaldataandthePowerPivotdatamodel.Chapter6focuseson
creatingandmanagingcalculationsandformulasinPowerPivot.Chapter7roundsout
PartIwithalookatpublishingyourPowerPivotreports.

PartII:WranglingDatawithPowerQuery
InPartII,youtakeanin-depthlookatthefunctionalityfoundinPowerQuery.
Chapters8and9presentthefundamentalsofcreatingqueriesandconnectingto
variousdatasources,respectively.Chapter10showsyouhowyoucanleveragePower
Querytoautomateandsimplythestepsforcleaningandtransformingdata.InChapter
11,youseesomeoptionsformakingqueriesworktogether.Chapter12wrapsupthis
lookatPowerQuerywithanexplorationofcustomfunctionsandadescriptionofhow
toleveragerecordedstepstocreateyourownamazingfunctions.

PartIII:ThePartofTens
PartIIIistheclassicPartofTenssectionfoundintitlesintheForDummiesseries.The
chaptersinthispartpresenttenormorepearlsofwisdom,deliveredinbite-sizepieces.
InChapter13,IsharewithyoutenwaystoimprovetheperformanceofyourPower
Pivotreports.Chapter14offersarundownoftentipsforgettingthemostoutofPower
Query.


IconsUsedInThisBook
Asyoulookinvariousplacesinthisbook,youseeiconsinthemarginsthatindicate
materialofinterest(ornot,asthecasemaybe).Thissectionbrieflydescribeseachicon
inthisbook.

Tipsarebeneficialbecausetheyhelpyousavetimeorperformataskwithout
havingtodoalotofextrawork.Thetipsinthisbookaretime-savingtechniques
orpointerstoresourcesthatyoushouldcheckouttogetthemaximumbenefit

fromExcel.

TrytoavoiddoinganythingmarkedwithaWarningicon,which(asyoumight
expect)representsadangerofonesortoranother.

Wheneveryouseethisicon,thinkadvancedtiportechnique.Youmightfind
thesetidbitsofusefulinformationjusttooboringforwords,ortheycouldcontain
thesolutionyouneedtogetaprogramrunning.Skipthesebitsofinformation
wheneveryoulike.

Ifyougetnothingelseoutofaparticularchapterorsection,rememberthe
materialmarkedbythisicon.Thistextusuallycontainsanessentialprocessora
bitofinformationyououghttoremember.

Paragraphsmarkedwiththisiconreferencethesamplefilesforthebook.If
youwanttofollowalongwiththeexamples,youcandownloadthesamplefilesat
www.dummies.com/go/powerpivotpowerqueryfd.Thefilesareorganizedby
chapter.


BeyondtheBook
Alotofextracontentthatyouwon’tfindinthisbookisavailableatwww.dummies.com.
Goonlinetofindthefollowing:
Excelfilesusedintheexamplesinthisbookcanbefoundat
www.dummies.com/go/excelpowerpivotpowerqueryfd

Onlinearticlescoveringadditionaltopicsareat
www.dummies.com/extras/excelpowerpivotpowerquery

Onthispage,youcanseehowtointegratePowerPivotandPowerQuerytocreate

adynamicreportingduo.Youcanalsouncoveralistofresourcestoaidyouinyour
PowerBIjourney.
TheCheatSheetforthisbookisat
www.dummies.com/cheatsheet/excelpowerpivotpowerquery

Onthispage,youfindalistofusefulPowerQueryfunctionsthatcanbeusedto
enhancethedataclean-upandtransformationprocess.
Updatestothisbook,ifwehaveany,arealsoavailableat
www.dummies.com/extras/excelpowerpivotpowerquery


WheretoGofromHere
It’stimetostartyourself-serviceBIadventure!Ifyou’reprimarilyinterestedinPower
Pivot,startwithChapter1.IfyouwanttodiverightintoPowerQuery,jumptoPartII,
whichbeginsatChapter8.


PartI


SuperchargedReportingwithPowerPivot

Gotowww.dummies.comforgreatDummiescontentonline.



Inthispart…
Discoverhowtothinkaboutdatalikearelationaldatabase.
GetasolidunderstandingofthefundamentalsofPowerPivotandpivottable
reporting.

UncoverthebestpracticesforcreatingcalculatedcolumnsandfieldsusingPower
Pivotformulas.
ExploreafewoptionsforpublishingyourPowerPivotreport.


Chapter1


ThinkingLikeaDatabase
InThisChapter
ExaminingtraditionalExcellimitations
Keepingupwithdatabaseterminology
Lookingintorelationships
Withtheintroductionofbusinessintelligence(BI)toolssuchasPowerPivotand
PowerQuery,it’sbecomingincreasinglyimportantforExcelanalyststounderstand
coredatabaseprinciples.UnliketraditionalExcelconcepts,wheretheapproachto
developingsolutionsisrelativelyintuitive,youneedtohaveabasicunderstandingof
databaseterminologyandarchitectureinordertogetthemostbenefitfromPower
PivotandPowerQuery.Thischapterintroducesyoutoahandfuloffundamental
conceptsthatyoushouldknowbeforetakingontherestofthisbook.


ExploringtheLimitsofExcelandHow
DatabasesHelp
Yearsofconsultingexperiencehavebroughtthishumbleauthorfacetofacewith
managers,accountants,andanalystswhoallhavehadtoacceptthissimplefact:Their
analyticalneedshadoutgrownExcel.Theyallfacedfundamentalchallengesthat
stemmedfromoneormoreofExcel’sthreeproblemareas:scalability,transparencyof
analyticalprocesses,andseparationofdataandpresentation.


Scalability
Scalabilityistheabilityofanapplicationtodevelopflexiblytomeetgrowthand
complexityrequirements.Inthecontextofthischapter,scalabilityreferstoExcel’s
abilitytohandleever-increasingvolumesofdata.MostExcelaficionadosarequickto
pointoutthatasofExcel2007,youcanplace1,048,576rowsofdataintoasingle
Excelworksheet—anoverwhelmingincreasefromthelimitationof65,536rows
imposedbypreviousversionsofExcel.However,thisincreaseincapacitydoesnot
solveallthescalabilityissuesthatinundateExcel.
Imaginethatyou’reworkinginasmallcompanyandusingExceltoanalyzeitsdaily
transactions.Astimegoeson,youbuildarobustprocesscompletewithallthe
formulas,pivottables,andmacrosyouneedinordertoanalyzethedatathatisstored
inyourneatlymaintainedworksheet.
Astheamountofdatagrows,youwillfirstnoticeperformanceissues.Thespreadsheet
willbecomeslowtoloadandthenslowtocalculate.Whydoesthishappen?Ithasto
dowiththewayExcelhandlesmemory.WhenanExcelfileisloaded,theentirefileis
loadedintoRAM.Exceldoesthistoallowforquickdataprocessingandaccess.The
drawbacktothisbehavioristhateverytimethedatainyourspreadsheetchanges,
ExcelhastoreloadtheentiredocumentintoRAM.Thenetresultinalargespreadsheet
isthatittakesagreatdealofRAMtoprocesseventhesmallestchange.Eventually,
everyactionyoutakeinthegiganticworksheetisprecededbyanexcruciatingwait.
Yourpivottableswillrequirebiggerpivotcaches,almostdoublingtheExcel
workbook’sfilesize.Eventually,theworkbookwillbecometoobigtodistributeeasily.
Youmayevenconsiderbreakingdowntheworkbookintosmallerworkbooks(possibly
oneforeachregion).Thiscausesyoutoduplicateyourwork.
Intime,youmayeventuallyreachthe1,048,576-rowlimitoftheworksheet.What
happensthen?Doyoustartanewworksheet?Howdoyouanalyzetwodatasetsontwo
differentworksheetsasoneentity?Areyourformulasstillgood?Willyouhaveto
writenewmacros?
Theseareallissuesthatneedtobeaddressed.
Ofcourse,youwillalsoencountertheExcelpowercustomers,whowillfindvarious

cleverwaystoworkaroundtheselimitations.Intheend,though,thesemethodswill


alwaysbesimplyworkarounds.Eventually,eventhesepower-customerswillbeginto
thinklessaboutthemosteffectivewaytoperformandpresentanalysisoftheirdata
andmoreabouthowtomakedata“fit”intoExcelwithoutbreakingtheirformulasand
functions.Excelisflexibleenoughthataproficientcustomercanmakemostthingsfit
justfine.However,whencustomersthinkonlyintermsofExcel,they’reundoubtedly
limitingthemselves,albeitinanincrediblyfunctionalway.
Inaddition,thesecapacitylimitationsoftenforceExcelcustomerstohavethedata
preparedforthem.Thatis,someoneelseextractslargechunksofdatafromalarge
databaseandthenaggregatesandshapesthedataforuseinExcel.Shouldtheserious
analystalwaysbedependentonsomeoneelseforherdataneeds?Whatifananalyst
couldbegiventhetoolstoaccessvastquantitiesofdatawithoutbeingreliantonothers
toprovidedata?Couldthatanalystbemorevaluabletotheorganization?Couldthat
analystfocusontheaccuracyoftheanalysisandthequalityofthepresentationinstead
ofroutingExceldatamaintenance?
Arelationaldatabasesystem(suchasAccessorSQLServer)isalogicalnextstepfor
theanalystwhofacesanever-increasingdatapool.Databasesystemsdon'tusually
haveperformanceimplicationswithlargeamountsofstoreddata,andarebuiltto
addresslargevolumesofdata.Ananalystcanthenhandlelargerdatasetswithout
requiringthedatatobesummarizedorpreparedtofitintoExcel.Also,ifaprocess
everbecomesmorecrucialtotheorganizationandneedstobetrackedinamore
enterprise-acceptableenvironment,itwillbeeasiertoupgradeandscaleupifthat
processisalreadyinarelationaldatabasesystem.

Transparencyofanalyticalprocesses
OneofExcel’smostattractivefeaturesisitsflexibility.Eachindividualcellcancontain
text,anumber,aformula,orpracticallyanythingelsethecustomerdefines.Indeed,
thisisoneofthefundamentalreasonsthatExcelisaneffectivetoolfordataanalysis.

Customerscanusenamedranges,formulas,andmacrostocreateanintricatesystemof
interlockingcalculations,linkedcells,andformattedsummariesthatworktogetherto
createafinalanalysis.
Sowhatistheproblem?Theproblemisthatthereisnotransparencyofanalytical
processes.Itisextremelydifficulttodeterminewhatisactuallygoingonina
spreadsheet.Anyonewhohashadtoworkwithaspreadsheetcreatedbysomeoneelse
knowsalltoowellthefrustrationthatcomeswithdecipheringthevariousgyrationsof
calculationsandlinksbeingusedtoperformanalysis.Smallspreadsheetsthatare
performingmodestanalysisarepainfultodecipher,andlarge,elaborate,multiworksheetworkbooksarevirtuallyimpossibletodecode,oftenleavingyoutostart
fromscratch.
ComparedtoExcel,databasesystemsmightseemrigid,strict,andunwaveringintheir
rules.However,allthisrigiditycomeswithabenefit.
Becauseonlycertainactionsareallowable,youcanmoreeasilycometounderstand
whatisbeingdonewithinstructureddatabaseobjectssuchasqueriesorstored


procedures.Ifadatasetisbeingedited,anumberisbeingcalculated,oranyportionof
thedatasetisbeingaffectedaspartofananalyticalprocess,youcanreadilyseethat
actionbyreviewingthequerysyntaxorthestoredprocedurecode.Indeed,ina
relationaldatabasesystem,youneverencounterhiddenformulas,hiddencells,ordead
namedranges.

Separationofdataandpresentation
Datashouldbeseparatefrompresentation;youdon’twantthedatatobecometootied
intoanyparticularwayofpresentingit.Forexample,whenyoureceiveaninvoice
fromacompany,youdon’tassumethatthefinancialdataonthatinvoiceisthetrue
sourceofyourdata.Itisapresentationofyourdata.Itcanbepresentedtoyouinother
mannersandstylesonchartsoronwebsites,butsuchrepresentationsareneverthe
actualsourceofthedata.
WhatexactlydoesthisconcepthavetodowithExcel?Peoplewhoperformdata

analysiswithExceltend,moreoftenthannot,tofusethedata,theanalysis,andthe
presentation.Forexample,youoftenseeanExcelworkbookthathas12worksheets,
eachrepresentingamonth.Oneachworksheet,dataforthatmonthislistedalongwith
formulas,pivottables,andsummaries.Whathappenswhenyou’reaskedtoprovidea
summarybyquarter?Doyouaddmoreformulasandworksheetstoconsolidatethe
dataoneachofthemonthworksheets?Thefundamentalprobleminthisscenariois
thattheworksheetsactuallyrepresentdatavaluesthatarefusedintothepresentationof
theanalysis.
Thepointbeingmadehereisthatdatashouldnotbetiedtoaparticularpresentation,
nomatterhowapparentlylogicalorusefulitmaybe.However,inExcel,ithappensall
thetime.
Inaddition,asdiscussedearlierinthischapter,becauseallmannersandphasesof
analysiscanbedonedirectlywithinaspreadsheet,Excelcannoteffectivelyprovide
adequatetransparencytotheanalysis.Eachcellhasthepotentialtoholdformulas,be
hidden,andcontainlinkstoothercells.InExcel,thisblursthelinebetweenanalysis
anddata,whichmakesitdifficulttodetermineexactlywhatisgoingonina
spreadsheet.Moreover,ittakesagreatdealofeffortinthewayofmanualmaintenance
toensurethateditsandunforeseenchangesdon’taffectpreviousanalyses.
Relationaldatabasesystemsinherentlyseparateanalyticalcomponentsintotables,
queries,andreports.Byseparatingtheseelements,databasesmakedatalesssensitive
tochangesandcreateadataanalysisenvironmentinwhichyoucaneasilyrespondto
newrequestsforanalysiswithoutdestroyingpreviousanalyses.
YoumayfindthatyoumanipulateExcel’sfunctionalitiestoapproximatethisdatabase
behavior.Ifso,youmustconsiderthatifyou’reusingExcel’sfunctionalitytomakeit
behavelikeadatabaseapplication,perhapstherealthingjustmighthavesomethingto
offer.Utilizingdatabasesfordatastorageandanalyticalneedswouldenhanceoverall
dataanalysisandwouldallowExcelpower-customerstofocusonthepresentationin
theirspreadsheets.



Inthesedaysofbigdata,customersdemandmore,notless,complexdataanalysis.
Excelanalystswillneedtoaddtoolstotheirrepertoirestoavoidbeingsimply
“spreadsheetmechanics.”Excelcanbestretchedtodojustaboutanything,but
maintainingsuchcreativesolutionscanbeatediousmanualtask.Youcanbesurethat
thesexyaspectofdataanalysisdoesnotlieintheroutinedatamanagementwithin
Excel;rather,itliesinleveragingBIToolssuchasprovidingclientswiththebest
solutionforanysituation.


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