Introduction to Solving Business Problems with MDX Robert Zare and Tom Conlon Program Managers Microsoft

Introduction to Solving Introduction to Solving Business Problems with MDXBusiness Problems with MDX

Robert Zare and Tom ConlonRobert Zare and Tom Conlon

Program ManagersProgram Managers

MicrosoftMicrosoft

AgendaAgenda

• MDX basicsMDX basics• Time series analysisTime series analysis• Multidimensional NavigationMultidimensional Navigation• Snapshot data analysisSnapshot data analysis

What is MDX?What is MDX?

• MDX is MDX is MMulti ulti DDimensional Eimensional EXXpressionspressions• MDX is the syntax for querying an Analysis MDX is the syntax for querying an Analysis

Services databaseServices database• MDX is part of the OLE DB for OLAP specMDX is part of the OLE DB for OLAP spec• MDX is the key for to utilizing the MDX is the key for to utilizing the

advanced analytical capabilities of advanced analytical capabilities of Analysis ServicesAnalysis Services

Comparison to SQLComparison to SQL

SQL ConstructSQL Construct OLAP constructOLAP construct

SELECT…SELECT… SELECT… SELECT… (MDX)(MDX)

FROMFROM FROM…FROM…(MDX)(MDX)

WHEREWHERE WHERE…WHERE…(MDX)(MDX)

CREATE…CREATE… DSO object modelDSO object model

DROP…DROP…

INSERT…INSERT…

DELETE…DELETE…

MDX basicsMDX basics

• MDX allows easy navigation in the multi MDX allows easy navigation in the multi dimensional spacedimensional space

• It “understands” the MD concepts of cube, It “understands” the MD concepts of cube, dimension, level, memberdimension, level, memberand celland cell

• It is used for It is used for – Queries – full statements (SELECT…FROM)Queries – full statements (SELECT…FROM)– Business modeling – definingBusiness modeling – defining

calculated members using MDX Expressions calculated members using MDX Expressions – – not a full statementnot a full statement

MDX Queries vs. MDX MDX Queries vs. MDX ExpressionsExpressions

• MDX QueriesMDX Queries– Full statements (SELECT…FROM)Full statements (SELECT…FROM)– Most often generated by end-user query tools Most often generated by end-user query tools

and applications such as Excel or Data and applications such as Excel or Data AnalyzerAnalyzer

– MDX Sample App deals in queriesMDX Sample App deals in queries• MDX Expressions MDX Expressions

– Partial MDX statements Partial MDX statements – Define an analytical object such as calculated Define an analytical object such as calculated

member, or named setmember, or named set– Return a single value (which may be a set)Return a single value (which may be a set)

MDX mythMDX myth

Fact: MDX is used everywhere:Fact: MDX is used everywhere: Calculated membersCalculated members Security settingsSecurity settings Custom member formulaCustom member formula Custom level formulaCustom level formula ActionsActions Named SetsNamed Sets Calculated CellsCalculated Cells

““Only developers need to know MDX”Only developers need to know MDX”

MDX constructsMDX constructs• Members: an item in a hierarchyMembers: an item in a hierarchy– [John Doe][John Doe]– [2001][2001]– [2001].[Q1].[Jan][2001].[Q1].[Jan]

• Tuple: an intersection of 2 or more membersTuple: an intersection of 2 or more members– ([Product].[Drink].[Beverages], [Customers].[USA])([Product].[Drink].[Beverages], [Customers].[USA])– ([Product].[Non-Consumable], [2001])([Product].[Non-Consumable], [2001])

• Sets: a group of tuples or membersSets: a group of tuples or members– {[John Doe], [Jane Doe]}{[John Doe], [Jane Doe]}– { ( [Non-Consumable], USA ), ( Beverages, Mexico ) }{ ( [Non-Consumable], USA ), ( Beverages, Mexico ) }– [2001].Children[2001].Children– TopCount(Store.[Store Name].Members, 10, Sales)TopCount(Store.[Store Name].Members, 10, Sales)

GroceriesGroceries

ClothingClothingAppliancesAppliances

SalesSales CostCostUnitsUnits

Every cell has a name...Every cell has a name...

19991999

20002000

20012001

19981998

19971997

MeasuresMeasures

Time

Time

Products

Products

GroceriesGroceries



(Products.Clothing, Measures.Units, Time.[2000])(Products.Clothing, Measures.Units, Time.[2000])


19991999

20002000

20012001

19981998

19971997

MeasuresMeasures

Time

Time

Products

Products

GroceriesGroceries




(Products.Clothing, Measures.Sales, Time.[1999])(Products.Clothing, Measures.Sales, Time.[1999])


19991999

20002000

20012001

19981998

19971997

MeasuresMeasures

Time

Time

Products

Products

GroceriesGroceries




(Products.Clothing, Measures.Sales, Time.[1999])(Products.Clothing, Measures.Sales, Time.[1999])

(Products.Groceries, Measures.Cost, Time.Year.[1997])(Products.Groceries, Measures.Cost, Time.Year.[1997])


19991999

20002000

20012001

19981998

19971997

MeasuresMeasures

Time

Time

Products

Products

19991999

20002000

20012001

GroceriesGroceries


SalesSales CostCost UnitsUnits

(Products.Clothing, Measures.Units, Time.[2000]) =(Products.Clothing, Measures.Units, Time.[2000]) =(Products.CurrentMember, (Products.CurrentMember,

Measures.CurrentMember, Measures.CurrentMember, Time.CurrentMember)Time.CurrentMember)

19981998

19971997

The current cell: CurrentMemberThe current cell: CurrentMember

20002000

ClothingClothing

SalesSales

??

Naming cells with relative Naming cells with relative references...references...

20002000

ClothingClothing

SalesSales

??

??

Naming cells with relative Naming cells with relative references...references...(Products.Clothing, Measures.Sales, Time.[2000].PrevMember)(Products.Clothing, Measures.Sales, Time.[2000].PrevMember)

20002000

ClothingClothing

SalesSales

??

??

??


(Products.Clothing, Measures.Sales, Time.[2000].NextMember)(Products.Clothing, Measures.Sales, Time.[2000].NextMember)

(Products.Clothing, Measures.Sales.PrevMember, Time.[2000].Lag(3))(Products.Clothing, Measures.Sales.PrevMember, Time.[2000].Lag(3))

20002000

ClothingClothing

SalesSales

??

??

??


(Products.Clothing, Measures.Sales, Time.[2000].NextMember)(Products.Clothing, Measures.Sales, Time.[2000].NextMember)

OROR

(Products.Clothing, (Products.Clothing, Measures.Sales.PrevMember,Measures.Sales.PrevMember,Time.[2000].Time.[2000].Lead(-3)Lead(-3)))

Calculated membersCalculated members

Calculated Calculated members add members add significant power to significant power to cubescubes

Pre-define complex Pre-define complex business logic (so business logic (so that user does not that user does not have to)have to)

Computed at run-Computed at run-timetime

AgendaAgenda• MDX basicsMDX basics• Time series analysisTime series analysis• Multidimensional NavigationMultidimensional Navigation• Snapshot data analysisSnapshot data analysis

1. How did Sales this period compare with Sales in 1. How did Sales this period compare with Sales in the previous period?the previous period?

YearYear QtrQtr MonMon SalesSales20002000 790790

Q1Q1 120120JanJan 3030FebFeb 4040MarMar 5050

Q2Q2 200200AprApr 6565MayMay 4545JunJun 9090

Q3Q3 185185JulJul 5555AugAug 6060SepSep 7070

Q4Q4 285285OctOct 8080NovNov 100100DecDec 105105

QtrQtr MonMon SalesSales DeltaDeltaQ2Q2 200200 8080

AprApr 6565 1515

MayMay 4545 -20-20

JunJun 9090 4545


(Time.CurrentMember, Measures.CurrentMember) =(Time.CurrentMember, Measures.CurrentMember) =


AprApr 6565 1515

MayMay 4545 -20-20

JunJun 9090 4545



(Time.CurrentMember, Measures.Sales) -(Time.CurrentMember, Measures.Sales) -


AprApr 6565 1515

MayMay 4545 -20-20

JunJun 9090 4545

(Time.CurrentMember.PrevMember, Measures.Sales)(Time.CurrentMember.PrevMember, Measures.Sales)



(Time.CurrentMember, Measures.Sales) (Time.CurrentMember, Measures.Sales) --

Calculated measure: [Sales Growth]Calculated measure: [Sales Growth]

2. How did Sales in the current period compare with Sales in the same 2. How did Sales in the current period compare with Sales in the same period last year?period last year?




20012001 850850 Q1Q1 170170

JanJan 5050FebFeb 5555MarMar 6565


YearYear QtrQtr MonMon SalesSales Annual DeltaAnnual Delta20002000 790790


20012001 850850 Q1Q1 170170

JanJan 5050 2020FebFeb 5555MarMar 6565

2. How did Sales in the current period compare with Sales in the 2. How did Sales in the current period compare with Sales in the same period last year?same period last year?

(Time.CurrentMember, Measures.Sales)-

(Time.CurrentMember.Lag(12), Measures.Sales)

YearYear QtrQtr MonMon SalesSales Annual DeltaAnnual Delta20002000 790790


20012001 850850 Q1Q1 170170

JanJan 5050 2020FebFeb 5555MarMar 6565

2. How did Sales in the current period compare with Sales in the 2. How did Sales in the current period compare with Sales in the same period last year?same period last year?

(ParallelPeriod(Year,1,Time.CurrentMember), Measures.Sales)

(Time.CurrentMember.Lag(12), Measures.Sales)

(Time.CurrentMember, Measures.Sales)-

Calculated measure: [Sales Growth Y/Y]Calculated measure: [Sales Growth Y/Y]

3. What have my sales been since the beginning of 3. What have my sales been since the beginning of the year?the year?






Time.Mar,Measures.Sales ...Time.Mar,Measures.Sales ...

Time.Jan,Measures.SalesTime.Jan,Measures.Sales ++Time.Feb,Measures.SalesTime.Feb,Measures.Sales ++

3. What have Sales been since the beginning of 3. What have Sales been since the beginning of the year?the year?

YearYear QtrQtr MonMon SalesSales YTDYTD20002000 790790

Q1Q1 120120 120120

JanJan 3030 3030

FebFeb 4040 7070

MarMar 5050 120120

Time.Mar,Measures.SalesTime.Mar,Measures.Sales

Time.Jan,Measures.SalesTime.Jan,Measures.Sales ++Time.Feb,Measures.SalesTime.Feb,Measures.Sales ++

3. What have Sales been since the beginning of 3. What have Sales been since the beginning of the year?the year?

==Sum(YTD(Time.CurrentMember), Sales)Sum(YTD(Time.CurrentMember), Sales)

YearYear QtrQtr MonMon SalesSales YTDYTD20002000 790790

Q1Q1 120120 120120

JanJan 3030 3030

FebFeb 4040 7070

MarMar 5050 120120

Calculated measure: [YTD Sales]Calculated measure: [YTD Sales]


Navigating the hierarchyNavigating the hierarchy(The Family Tree)(The Family Tree)

Jan F eb M a r

Q 1 Q 2 Q 3

O c t N o v D e c

Q 4

2 000

Q 1 Q 2 Q 3 Q 4

2 001

A ll

ParentsParents

Jan F eb M a r

Q 1 Q 2 Q 3

O c t N o v D e c

Q 4

2 000

Q 1 Q 2 Q 3 Q 4

2 001

A llTime.[2000].ParentTime.[2000].Parent

ParentsParents

Jan F eb M a r

Q 1 Q 2 Q 3

O c t N o v D e c

Q 4

2 000

Q 1 Q 2 Q 3 Q 4

2 001

A llTime.[2000].ParentTime.[2000].Parent Time.[2001].ParentTime.[2001].Parent

ParentsParents

Jan F eb M a r

Q 1 Q 2 Q 3

O c t N o v D e c

Q 4

2 000

Q 1 Q 2 Q 3 Q 4

2 001

A ll

Time.[2000].FirstChildTime.[2000].FirstChild

ChildrenChildren

Jan F eb M a r

Q 1 Q 2 Q 3

O c t N o v D e c

Q 4

2 000

Q 1 Q 2 Q 3 Q 4

2 001

A ll

Time.[2000].FirstChildTime.[2000].FirstChild

ChildrenChildren

Jan F eb M a r

Q 1 Q 2 Q 3

O c t N o v D e c

Q 4

2 000

Q 1 Q 2 Q 3 Q 4

2 001

A ll

Time.[2000].ChildrenTime.[2000].Children

ChildrenChildren

Jan F eb M a r

Q 1 Q 2 Q 3

O c t N o v D e c

Q 4

2 000

Q 1 Q 2 Q 3 Q 4

2 001

A ll

Descendants( Time.Descendants( Time.[2000], Quarter) [2000], Quarter)

Descendants Descendants

Jan F eb M a r

Q 1 Q 2 Q 3

O c t N o v D e c

Q 4

2 000

Q 1 Q 2 Q 3 Q 4

2 001

A ll

Descendants( Time.[2000], Month) Descendants( Time.[2000], Month)


Jan F eb M a r

Q 1 Q 2 Q 3

O c t N o v D e c

Q 4

2 000

Q 1 Q 2 Q 3 Q 4

2 001

A ll

Descendants(Time.[2000].[Jan], Descendants(Time.[2000].[Jan], Month) Month)


Jan F eb M a r

Q 1 Q 2 Q 3

O c t N o v D e c

Q 4

2 000

Q 1 Q 2 Q 3 Q 4

2 001

A ll

Descendants(Time.[2000].[Jan], Descendants(Time.[2000].[Jan], Month) Month)



The Inventory ProblemThe Inventory Problem

• A set of inventory snapshots over timeA set of inventory snapshots over time– DimensionsDimensions• Products: (All), Family, Category, NameProducts: (All), Family, Category, Name• Warehouses: (All), WarehouseWarehouses: (All), Warehouse• Time: Year, Quarter, MonthTime: Year, Quarter, Month• Store: (All), Country, City, StoreStore: (All), Country, City, Store

– MeasuresMeasures• Quantity [default aggregation=sum]Quantity [default aggregation=sum]

– The problem:The problem:• Measures are not additive over timeMeasures are not additive over time

The inventory problem: Semi-additive measuresThe inventory problem: Semi-additive measures

YearYear QtrQtr MonthMonth QuantityQuantity20002000 790790





Problem: Problem: Quantity is not Quantity is not additive over additive over

timetime

Business solutions…Business solutions…

1.1. Average quantities in each time periodAverage quantities in each time period

2.2. Opening and closing balances for each Opening and closing balances for each time periodtime period

3.3. Minimum and maximum inventory levels in Minimum and maximum inventory levels in a time perioda time period

1. Average over time1. Average over time

1.1. Sum of quantities over all months in the Sum of quantities over all months in the period, divided by the number of months in period, divided by the number of months in the periodthe period

2.2. Sum(Sum( months in the period months in the period , , Quantity) / Count(Quantity) / Count( months in the months in the period period ))

3.3. Sum(Descendants( Time.CurrentMemSum(Descendants( Time.CurrentMember,[Month]), Quantity) / ber,[Month]), Quantity) / Count(Descendants( Time.CurrentMCount(Descendants( Time.CurrentMember,[Month]))ember,[Month]))

4.4. AvgAvg(( Descendants( Time.CurrentMe Descendants( Time.CurrentMember,[Month]), Quantitymber,[Month]), Quantity))

Calculated measure: [Average balance]Calculated measure: [Average balance]

2. Closing period inventory value… 2. Closing period inventory value…

YearYear QtrQtr MonthMonth QtyQty CalcCalc20002000 790790 105105

Q1Q1 120120 5050JanJan 3030 3030FebFeb 4040 4040MarMar 5050 5050

Q2Q2 200200 9090AprApr 6565 6565MayMay 4545 4545JunJun 9090 9090

Q3Q3 185185 7070JulJul 5555 5555AugAug 6060 6060SepSep 7070 7070

Q4Q4 285285 105105OctOct 8080 8080NovNov 100100 100100DecDec 105105 105105

2. Closing balance2. Closing balance

1.1. Quantity of the last month in the periodQuantity of the last month in the period

2.2. Quantity of the last item inQuantity of the last item in((Descendants(Time.CurrentMember, Descendants(Time.CurrentMember, [Month][Month]))

3.3. ((TailTail( ( Descendants( Time.CurrentMDescendants( Time.CurrentMember, [Month]ember, [Month])), 1), , 1), Measures.QuantityMeasures.Quantity))

4.4. ((ClosingPeriod([Month], ClosingPeriod([Month], Time.CurrentMember),Time.CurrentMember), Measures.QuantityMeasures.Quantity))

Calculated measure: [Closing Balance]Calculated measure: [Closing Balance]

3. Maximum Quantity During the 3. Maximum Quantity During the PeriodPeriod

• We want the Maximum monthly inventory We want the Maximum monthly inventory value for each periodvalue for each period

• MaxMax(( Descendants( Time.CurrentMember Descendants( Time.CurrentMember, Month), Measures.Quantity , Month), Measures.Quantity ))– Why did we calculate using Descendants(…, Why did we calculate using Descendants(…,

Month)? Why not use the Children function?Month)? Why not use the Children function?

Calculated measure: [Maximum Quantity]Calculated measure: [Maximum Quantity]

SummarySummary

• MDX is everywhereMDX is everywhere

• Calculated members are the most common Calculated members are the most common application of MDX in cube modelingapplication of MDX in cube modeling

• Understand the fundamental concepts: Understand the fundamental concepts: CurrentMemberCurrentMember, , .Parent.Parent, , .Children.Children, , DescendantsDescendants, etc. as these are the building , etc. as these are the building blocks for many expressionsblocks for many expressions

More InformationMore Information

• BooksBooks– Step by Step Analysis ServicesStep by Step Analysis Services

• JacobsenJacobsen

– Microsoft OLAP SolutionsMicrosoft OLAP Solutions• Thomsen, Spofford, ChaseThomsen, Spofford, Chase

– MDX SolutionsMDX Solutions• SpoffordSpofford

• OnlineOnline– Public NewsgroupPublic Newsgroup

• Microsoft.public.sqlserver.olapMicrosoft.public.sqlserver.olap

– MSN CommunityMSN Community• http://groups.msn.com/http://groups.msn.com/

MicrosoftOLAPServicesUsersCommunity/_homepage.msnw?MicrosoftOLAPServicesUsersCommunity/_homepage.msnw?pgmarket=en-uspgmarket=en-us

– Microsoft.comMicrosoft.com• http://microsoft.com/sql/evaluation/bi/default.asphttp://microsoft.com/sql/evaluation/bi/default.asp

Don’t forget to complete the Don’t forget to complete the on-line Session Feedback form on-line Session Feedback form on the Attendee Web siteon the Attendee Web site

https://web.mseventseurope.com/teched/https://web.mseventseurope.com/teched/

https://web.mseventseurope.com/teched/

Documents

Introduction to Solving Business Problems with MDX Robert Zare and Tom Conlon Program Managers Microsoft