51 bi sap bi modeling
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SAP BW Data Modeling
SAP University AlliancesVersion 2.0Authors Klaus Freyburger
Peter Lehmann
© 2010 All Rights Reserved. SAP UA
Abstract:This chapter covers the basic aspects and concepts of data modeling with SAP Business Information Warehouse (SAP BW).
ProductSAP Netweaver BI 7.0
LevelUndergraduateBeginner
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
• Overview• InfoObjects
– Key Figures– Characteristics
• InfoProviders– DataStore Objects
Agenda
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j– InfoCubes
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
SAP BW Architecture Overview
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SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
SAP BW Data Modeling Architecture Objects and Data Structures
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SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
What is an InfoObject?
• InfoObjects are used to focus on business requirements.– Note:
• The original product name was “SAP Business InformationWarehouse.”
• The abbrevation “BIW” conflicted with another product name, so “BW” was chosen.
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• InfoObjects are the “bricks” to build data structures inside SAP BW.– InfoObjects represent business objects from an end user’s
view.– The most important InfoObject types used for business analysis
are Characteristics and Key Figures.
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
InfoObject: Characteristics
• A Characteristic represents a business object (or concept, business term, business entity).– A Characteristic may have attributes which describes the
business object in more detail.– Example: InfoObject “Customer” is a characteristic with
attributes such as “Customer Number”, “ZIP Code”, “Region”,
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, , g ,etc.
– The attributes “Customer Number”, “ZIP Code”, “Region”, etc. are also managed as Characteristics and may have their own attributes.
Note: What SAP calls a Characteristic is often referred to in the data warehouse community as a Dimension.
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SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
InfoObject: Key Figures
• A Key Figure (or variable, measure) is oftenly used to document the performance of a business process over time.– It can be found in document records such as invoice, delivery
note, purchase order, or goods receipt.– Example: InfoObject “Revenue” or “Sales Amount”, etc.
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• Note: InfoObjects are unique inside SAP BW, and they are used to build the data structures for analysis requirements.– Conceptually unique: the semantics (meaning) of an
InfoObject is uniquely defined system-wide inside SAP BW.– Logically unique: the data type, value range or field length is
uniquely defined system-wide inside SAP BW.– From the technical point of view, an InfoObject can viewed as a
database field.
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Evolution from a SAP ERP Database Object to an SAP BW InfoObject
R/3
Table Costcenter
BW ExtraktorSAP ERPSAP BW InfoObjects
SAP BW DataSource
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InfoObject"0COSTCENTER"
SAP Business Information Warehouse!!
COAccounting
COAccounting
HRHuman
Ressources
HRHuman
Ressources
COSTC ...
Table Costcenter
Table EmployeeEMPLO COST_CENTER ...
DataSourceCostCenter
Definition&
Mapping
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
InfoObjects Are “Bricks” for Data Structures
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SAP UA
InfoProviders “Provide” Access to Data Records
InfoProviders:• Are data storage inside SAP BW• May store data records physically (persistent)• May also be used to access data stored outside SAP BW virtually
(transparent views)• May be accessed with front end tools such as SAP
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• May be accessed with front end tools such as SAP BusinessExplorer
Note: A query is a “view” to data within an InfoProvider and does not contain physical data.
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
InfoProviders
• InfoProviders with physical data: – InfoCubes
• Contain data optimized for fast multi-dimensional analysis.– DataStore Objects
• Contain detailed data.• Used for high data volumes stored in normal database tables.
Oft d “d t ” f I f C b
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• Often used as “data source” for InfoCubes.
• InfoProviders with virtual data:– MultiProviders
• Often used to create “views” above two or more InfoCubes with the same Characteristics but different Key Figures.
• Data resides in the InfoCubes involved and data redundancy is avoided.– VirtualProviders
• Data stored somewhere outside SAP BW. • Some ERP systems provide data storage which may be accessed directly
by SAP BW without changing the end user ‘s view to the data.
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
InfoCubes
• Provide data storage used for reporting and online analysis.
• Consist of Key Figures and Characteristics.• Contain data stored multi-dimensionally and often aggregated
(week, month).• Use star database schema consisting of a fact table surrounded
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Use star database schema, consisting of a fact table surrounded by dimension tables.
• Use a maximum of 3 + 13 dimension tables.– 3 dimension tables are pre-defined by SAP.
• Time, Unit and DataPackage (for technical information)– 13 dimensions may be used by InfoCube developers.
Note: In practice, good InfoCube design should not exceed 6-8 dimensions (+ the 3 above) so 13 dimensions are plenty.
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SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
DataStore Objects
• Contain single data records such as invoices, purchase orders or customer order items.
• Consist of key fields (such as “order number”, “order position number”) and data fields (Key Figures and Characteristics such as “sales amount”, “ net value”, “customer id”, “material number”).
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• Store data records in relational database tables.• Often contain massive volumes of data.
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
InfoCube versus DataStore Object
• Data Warehouse, Operational Data Store and Data Marts are general layers in a Data Warehouse Architecture.
BI1-M2-01-Data Warehouse
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• Data Warehouse and Operational Data Store may be implemented with DataStoreObjects.
• Data Marts will be implemented with InfoCubes.
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
• Overview• InfoObjects
– Key Figures– Characteristics
• InfoProviders– DataStore Objects
Agenda
Page 15© 2010 SAP AG
j– InfoCubes
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SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
InfoObjects
• InfoObjects– Key Figures
• Revenue, Sales Amount, Net Value, ….– Characteristics
• Customer, Region, Zip Code, …Units
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– Units• Unit of Measurement, Currency, …
– Time• Calender Year, Fiscal Year, Month, Day, Quarter, ….
– Some Technical Stuff• DataPackageID, RequestID, …
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Key Figure Definition: Revenue
Amount, Quantity, .. …
Data Type: integer,
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EUR, USD, … (fix)
Pieces, inch, %, … (fix)
Unit / Currency (fix) / Currency reference
Data Type: integer, float, char(10), …
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Key Figure Definition: Revenue (cont.)
Aggregation: Last Value,
Jan Feb Mar Apr May Jun
500520 515 520 520
Last valueNo Employee per Month
521
Last value
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Aggregation: Summation, Minimum, Maximum
gg g ,Maximum, Average…
Reference Characteristic, e.g. QuarterThe reference characteristic allows the use of a function to aggregate data instead of summation.Example: Number of Employees at the end of the quarter. Sum does not make sense!
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Key Figure Definition: Revenue (cont.)
If the Key Figure is non-cumulative (e.g., warehouse stock), this field defines an InfoObject representing non-cumulative change. This
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InfoObject is either positive or negative. So, the stock amount can be calculated from it. Two fields are used to
calculate the non-cumulative amounts. Inflow is the InfoObject which represents the stock inflow amount. Outflow is vice versa.
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Key Figure Definition: Revenue (cont.)
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SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Characteristic Definition: Sales Organisation
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Data Types: Num, Char, Date, …
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SAP UA
Conversion Routine
Database values• Are stored in internal format
appropriate to the database– Date as YYYYMMDD
• Are presented to a user in external format according to his local settings, e.g., in
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g ,– Europe
• Date: DD.MM.YYYY• Numbers: 1.234,56
– US• Date: MM/DD/YYYY• Numbers: 1,234.56
Transformation external internal format is performed by a conversion routine
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
ALPHA Conversion Routine
Alphanumeric database fields• Datatype CHAR in SAP• Can store character and number values• Have conversion exit ALPHA as default
– Eliminates leading blanks after user input• User input of ‚RB0010‘ and ‚ RB0010‘ refers to same object
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p j– Stores numbers with leading 0s in database
• Numeric values are stored in natural order in database, e.g. 0002 first, then 0010
Material Group in SAP Business Content has numerical values with trailing blanksConversion exit ALPHA must not be used
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
MATN1 Conversion Routine
Database field Material often requires special treatment.• Datatype CHAR in SAP• Conversion exit MATN1 is used• Edit format can be defined in transaction OMSL
– E.g. _ _-_ _ _ _ User Input RB-0010 is stored as RB0010
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Since the OMSL format setting is system-wide, we do not use it in the Bike Company Curriculum.
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SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Characteristic Definition: Sales Organisation (cont.)An InfoObject may
have attributes!
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Texts:Descriptive textsMulti-language textsTime dependent texts
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Characteristic Definition: Sales Organisation (cont.)
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Attributes
Usable for OLAP operations or display only
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Time Characteristics
• Time characteristics are always necessary and define the time-related reference point for data analysis purposes.
• Time characteristics are predefined by SAP and cannot
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be changed.
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SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Units/Currencies
• Units and Currencies are used to define Key Figures in more detail.• A Unit may be an InfoObject which defines the Unit of a Key Figure.• A Currency may be an InfoObject which defines the Currency of a
Key Figure• Examples:
0CURRENCY
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– 0CURRENCY – 0BASE_UOM
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
• Overview• InfoObjects
– Key Figures– Characteristics
• InfoProviders– DataStore Objects
Agenda
Page 29© 2010 SAP AG
j– InfoCubes
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
5 Steps to Define a DataStore Object
5 steps to Define an DataStore Object1) Define a name for a
DataStoreObject2) Choose the key fields3) Choose the data fields4) Define attributes used for data
l i
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analysis5) Activate the DataStoreObject
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SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Choosing InfoObjects to Build a DataStore Object
• Select the relevant InfoObjects– Direct InfoObject name input (1) or– Choose InfoObjects by InfoObjectCatalog and drag & drop the
InfoObjects (2)
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SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
7 Steps to Define an InfoCube
7 Steps to Define an InfoCube1) Choose a name for an InfoCube2) Create Dimensions as needed3) Assign Characteristics to Dimensions4) Choose Time Characteristics5) Choose Key Figures
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5) C oose ey gu es6) Define Navigational Attributes7) Activate InfoCube
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Create New Dimensions If Needed
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SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
What is a Dimension Inside SAP BW?
• A dimension is a group of characteristics which belong to the same business object (semantically).
• Each characteristic may contain additional attributes which are relevant for data analysis – or not!!!
Navigational attributes are InfoObjects which are used to perform data analysis.
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Display attributes are InfoObjects for which data analysis does not make sense (e.g. a house number or a family name)
This has an impact to cube design!
Note: In data warehouse community, the term Dimension is used for what SAP calls Characteristic .
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Excursion: SAP BW - Enhanced Star Schema
• Attributes are not part of a dimension!
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DimensionCharacteristic as part
of a dimension
Characteristic as navigation attribute
NAV
NAV
NAV
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Displayed in the Frontend Tool
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SAP UA
Basic Characteristic and Its Navigation Attributes
1 Dimension
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2. Characteristic
1. Dimension
3. Navigation Attributes are ready to be used in analysis.
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Steps to Create an InfoCube
• Define the InfoObjects needed.– Key Figures– Characteristices
• Define which Characteristics may be chosen to create a semantic cluster for semantic dimensions.– Examples are: Sales, Production, Material Management, Finance, etc.
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Examples are: Sales, Production, Material Management, Finance, etc.• Define which attributes are appropriate to perform data analysis
– OLAP attributes define them as “navigational” attributes – Non-OLAP attributes define them as “display” attributes
• Done! Deploy the InfoCube inside SAP BW!
SAP BI Curriculum BI2-M2 SAP BW Data Modeling
SAP UA
Summary
• Key Figures and Characteristics are defined as InfoObjects.• InfoObjects are the smallest “bricks” to define InfoProviders
within SAP BW.• InfoProviders are used to store data within SAP BW or allow SAP
BW to access data stored somewhere else.• The most important InfoProviders are InfoCubes
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The most important InfoProviders are InfoCubesand DataStore Objects.
• The definition of an SAP BW InfoCube isno Witchery!