SAP BW IQ - Part 2

11. What is the difference between V1, V2 and V3 updates? 

A:  V1 Update: It is a Synchronous update. Here the Statistics update is 
     carried out at the same time as the document update (in the application 
     tables).

     

     V2 Update: It is an Asynchronous update. Statistics update and the 
     Document update take place as different tasks.

 V1 and V2 don't need scheduling.

   Serialized V3 Update: The V3 collective update must be scheduled as a job 
   (via LBWE). Here, document data is collected in the order it was created and 
   transferred into the BW as a batch job. The transfer sequence may not be the 
   same as the order in which the data was created in all scenarios. V3 update 
   only processes the update data that is successfully processed with the V2 
   update.

12. What is compression?

A:  It is a process used to delete the Request IDs and this saves space.

13. What is Rollup?
 

A: This is used to load new DataPackages (requests) into the InfoCube   
    aggregates.
   
    If we have not performed a rollup then the new InfoCube data will not be 
    available while reporting on the aggregate.

14. What is table partitioning and what are the benefits of partitioning 
      in an InfoCube?

A:  It is the method of dividing a table which would enable a quick reference. 
     SAP uses fact file partitioning to improve performance. 

     We can partition only at 0CALMONTH or 0FISCPER.

     Table partitioning helps to run the report faster as data is stored in the 
     relevant partitions. 

     Also table maintenance becomes easier.

     Oracle, Informix, IBM DB2/390 supports table partitioning while SAP DB, 
     Microsoft SQL Server, IBM DB2/400 do not support table portioning.

15. How many extra partitions are created and why?

A:  Two partitions are created for date before the begin date and after the end 
     date.

16. What are the options available in transfer rule?
 
A:   InfoObject

      Constant

      Routine
      Formula

17. How would you optimize the dimensions?
 
A:  We should define as many dimensions as possible and we have to take care 
     that no single dimension crosses more than 20% of the fact table size.

18. What are Conversion Routines for units and currencies in the 
      update rule?

 A:  Using this option we can write ABAP code for Units / Currencies conversion.

      If we enable this flag then unit of Key Figure appears in the ABAP code as   
     an additional parameter. For example, we can convert units in Pounds to 
     Kilos.

19. Can an InfoObject be an InfoProvider, how and why?


A:  Yes, when we want to report on Characteristics or Master Data. 
     
     We have to right click on the InfoArea and select "Insert characteristic as    
     data target". 

     For example, we can make 0CUSTOMER as an InfoProvider and report on it.

20. What is Open Hub Service?
 
A:  The Open Hub Service enables us to distribute data from an SAP BW system 
     into external Data Marts, analytical applications, and other applications. 

     We can ensure controlled distribution using several systems. 
     The central object for exporting data is the InfoSpoke. 

    We can define the source and the target object for the data. BW becomes a 
    hub of an enterprise data warehouse. 

    The distribution of data becomes clear through central monitoring from the 
    distribution status in the BW system.