Definitions of some Objects in BI/BW

Info Area:

Element for grouping meta-objects in the BI system.

Each InfoProvider is assigned to an InfoArea. The resulting hierarchy is displayed in the Data Warehousing Workbench.

In addition to their properties as an InfoProviders, InfoObjects can also be assigned to different Info Areas.
Info Area is a Top Level Object, which contains the data models in it .


In general, Info Areas are used to organize InfoCubes and InfoObjects. Each InfoCube is assigned to an Info Area. Through an InfoObject Catalog, each Info Object is assigned to an Info Area as well.


The Info Area contains all objects used to evaluate for a business logical process.


Info Area in which Info Providers are stored.


Info Object Catalogs:


An Info Object catalog is a collection of InfoObjects grouped according to application-specific criteria. 


There are two types of InfoObject catalogs: Characteristic and Key figure.


Info Objects, (characteristics and key figures) are the basic data model of SAP Business information warehouse(BW/BI).


And the Info objects are stored in folders, it also called the “InfoObject catalogs”, the infoobject catalogs are also stored in a folder called Info Areas.


An Info Object catalog is assigned to an Info Area.


An Info Object can be included in several Info Object catalogs.


Info Objects:


Business evaluation objects are known in BI/BIW as InfoObjects. They are divide into characteristics (for example, customers), key figures (for example, revenue), units (for example, currency, amount unit), time characteristics (for example, fiscal year) and technical characteristics (for example, request number). 


Info Objects are the smallest information units in BI/BW.


They structure the Information needed to create the data targets.

Info Objects with attributes or texts can be either a pure data target or an Info Provider (if it is being reported).

Application Component

Application Components are used to organize Data Sources. They are analogous to the Info Areas .

DataSource

A DataSource is not only a structure in which source system fields are logically grouped together, but also an object that contains ETTL-related information.
 Four types of DataSources exist:
DataSources for transaction data
DataSources for characteristic attributes
DataSources for characteristic texts
DataSources for characteristic hierarchies

If the source system is R/3, replicating DataSources from a source system will create identical DataSource structures in the BI/BW system. 

Info Package:
An InfoPackage specifies when and how to load data from a given source system. BW generates a 30-digit code starting with ZPAK as an InfoPackage's technical name.

PSA

Persistent Staging Area is a data staging area in BW. It allows us to check data in an intermediate location, before the data are sent to its destinations in BW.
The PSA stores data in its original source system format. In this way, it gives us a chance to examine / analyse the data before we process them to further destinations. Most probably it is a temporary storage area, based on the client data specifications and settings.
SID
SID (Surrogate-ID) translates a potentially long key for an InfoObject into a short four-byte integer, which saves I/O and memory during OLAP.

Star schemaA star schema is a technique used in the data warehouse database design to help data retrieval for online analytical processing(OLAP).

Business Content

Business Content is a complete set of BI/BW objects developed by SAP to support the OLAP tasks. It contains roles, workbooks, queries, Info Cubes, key figures, characteristics, Transformations and extractors for SAP R/3, and other mySAP solutions.

Compound attribute

A compound attribute differentiates a characteristic to make the characteristic uniquely identifiable. For example, if the same characteristic data from different source systems mean different things, then we can add the compound attribute 0SOURSYSTEM (source system ID) to the characteristic; 0SOURSYSTEM is provided with the Business Content.

Data packet size

For the same amount of data, the data packet size determines how work processes will be used in data loading. The smaller the data packet size, the more work processes needed.

Data Warehouse

Data Warehouse is a dedicated reporting and analysis environment based on the star schema database design technique and requiring special attention to the data ETTL process.

Delta update

The Delta update option in the InfoPackage definition requests BI/BW to load only the data that have been accumulated since the last update. Before a delta update occurs, the delta process must be initialized.

Connecting Master Tables to InfoCubes Via SID Tables

In order to cover the re-alignment of master data attributes, the master data tables in a BI Data model are not linked directly to Info Cubes ( but connected via Surrogate Keys ) as the following, simplified, picture below explains:

As you can see, pointer or translation tables called SID (Surrogate-ID) tables are used in the BI data model to link the master tables of the BI data model to Info Cubes.

The above graphic shows a simplified version of what types of SID tables exist .

SID Tables

SID tables play an important role in linking the data warehouse information structures to the InfoCubes and Data Store Objects. To speed up access to InfoCubes and DataStore Objects and to allow an independent master data layers, each characteristic and attribute is assigned a SID column and their values are encoded into 4-byte integer values.

InfoObject definition and SID tables

To offer optimal performance with the various data models with respect to master data access, three different SID tables might be generated.

SID tables with respect to master data:

•  The SID table is always generated if an InfoObject is not defined as ‘attribute only’ (tab page general).This table is used if the access to an Infocube or DataStore Object uses a navigational attribute or if the access is via a characteristic without attributes. Name of the table: /BIC/S
• 
  
• The non-time dependent attribute SID table of a characteristic for access via non-time dependent attributes. Name of the table: /BIC/X
• 
  
• The time dependent attribute SID table of a characteristic for access via time dependent attributes.Name of the table: /BIC/Y

All these SID tables are automatically maintained during master data load. SID tables are also maintained

during InfoCube load if no referential integrity check is enforced (InfoPackage).


But in case of Line Item Dimension the SID table acts as a Dimension Tables, that means NO Dimension table is created for this .



Dimensions with only one characteristic (line item dimensions)
It is very often possible in this model to assign only one characteristic to a dimension.This will probably occur with specific reporting requirements or if for example you have the document line item in your model which occupies lot of space of Fact table. In these situations a dimension table means only overhead. BI allows you define this kind of dimension as a line item dimension (Check box dimension definition while creation of Info cube). In doing this no dimension table will be generated for this dimension. As dimension table will serve the SID table of this characteristic. The key in the fact table will be the SID of the SID Table.

pictures explains