When implementing only APO-DP with R/3: 
How do you propose to deal with materials (characteristic value combinations in APO-DP)  that are not required anymore in the Forecasting process ? 
We upload the 'actual demand' from an SIS info structure to an InfoCube and from there to a planning area. 
When we have, for example, an obsolete product  in R/3 then we don't want it to be in APO-DP (could effect the calculation of propotions est...). 
Is there a way to 'clean' the cube and the planning area based on, for example, marking a material in R/3 as obsolete? I assume you had to deal with similar issues. 
Any ideas and/or documents on this issue ? 
 

Try SE38 ABAP Editor --> RSDRD_DELETE_FACTS.  This will allow you to create a program for deleting entries in a fact table of a cube or planning area.

1.  Select the infocube
2.  Select radio button "Generate deletion program"
3.  Name of Report (specify the name that you would like for your program i.e. DELETE_OLD_FCST)
4.  Copy the name of your program for easy entry below
5.  Click the "execute" button
6.  Back out using the green arrow
6.  Paste or use the pulldown to find the new program

This will allow you to be selective in characteristic combinations that you want to delete without affecting other master data.

Can some one help me for calculating safety stock in supply network planning. 

I have done all set up required for calculating the safety stock. I am using 9asnp02 planning area. I have demand data available for each period. Transaction code used is /sapapo/msdp_sb. 

Execute transaction with result log gives all details of demand in each bucket but the safety stock is zero even though, demand is available at location.In product master data service level, stock method and target days supply are already maintained.
 

Have you tried the safety stock set up via the product data already? You could first try this to make sure you get some results. Use the lot size tab in the product data.
 

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