What is the purpose of setup tables?

Setup tables are kind of interface between the extractor and application tables. LO extractor takes data from set up table while initalization and full upload and hitting the application table for selection is avoided. As these tables are required only for full and init load, you can delete the data after loading in order to avoid duplicate data. Setup tables are filled with data from application tables.The setup tables sit on top of the actual applcation tables (i.e the OLTP tables storing transaction records).  During the Setup run, these setup tables are filled. Normally it's a good practice to delete the existing setup tables before executing the setup runs so as to avoid duplicate records for the same selections

We are having Cube. what is the need to use ODS. what is the necessary to use ODS though we are having cube?

1)  Remember cube has aggregated data and ods has granular data. 
2)  In update rules of a infocube you do not have option for over write whereas for a ods the default is overwrite.

What is the importance of transaction RSKC? How it is useful in resolving the issues with speial characters.

How to handle double data loading in SAP BW?

What do you mean by SAP exit, User exit, Customer exit?

What are some of the production support isues-trouble shooting guide?

When we go for Business content extraction and when go for LO/COPA extraction?

What are some of the few infocube name in SD and MM that we use for extraction and load them to BW?

How to create indexes on ODS and fact tables?

What are data load monitor (RSMO or RSMON)?

1A. RSKC.

Using this T-code, you can allow BW system to accept special char's in the data coming from source systems.  This list of chars can be obtained after analyzing source system's data OR can be confirmed with client during design specs stage.

2A. Exit.s

These exits are customized for handling data transfer in various scenarios. 
(Ex. Replacement Path in Reports- > Way to pass variable to BW Report)
Some can be developed by BW/ABAP developer and inserted wherever its required.

Some of these programs are already available and part of SAP Business Content. These are called SAP Exits. Depends on the requirement, we need to extend some exits and customize.

3A. 

Production issues are different for each BW project and most common issues can be obtained from some of the previous mails. (data load issues).

4A. 

LIS Extraction is kind of old school type and not preferred with big BW systems.  Here you can expect issues related to performance and data duplication in set up tables.

LO extraction came up with most of the advantages and using this, you can extend exiting extract structures and use customized data sources.

If you can fetch all required data elements using SAP provided extract structures, you don't need to write custom extractions... You can get clear idea on this after analyzing source system's data fields and required fields in target system's data target's structure.

5A.

MM -  0PUR_C01(Purchasing data) , OPUR_C03 (Vendor Evaluation) 
SD  -  0SD_CO1(Customer),0SD_C03( Sales Overview) ETC..

6A. 

You can do this by choosing "Manage Data Target" option  and click on few buttons available in "performance" tab. 

7A.

RSMO is used to monitor data flow to target system from source system. You can see data by request, source system, time request id etc.... just play with this..

Tips by : Anand, Shishir

What is KPI?

A KPI are Key Performance Indicators.
These are values companies use to manage their business.  E.g. net profit.

In detail: 

Stands for Key Performance Indicators. A KPI is used to measure how well an organization or individual is accomplishing its goals and objectives. Organizations and businesses typically outline a number of KPIs to evaluate progress made in areas where performance is harder to measure. 

For example, job performance, consumer satisfaction and public reputation can be determined using a set of defined KPIs. Additionally, KPI can be used to specify objective organizational and individual goals such as sales, earnings, profits, market share and similar objectives. 

KPIs selected must reflect the organization's goals, they must be key to its success, and they must be measurable. Key performance indicators usually are long-term considerations for an organization.         *-- Anoo

Related

• SAP BW Interview Questions 1
• SAP BW Interview Questions 2

SAP Business Warehouse Books
SAP BW Books - Certification, Interview Questions and Configuration

SAP BW Tips
SAP BW Tips and Business Information Warehouse

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SAP Basis, ABAP Programming and Other IMG Stuff
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