Configuring delta load from totals transaction cube in BCS

Hello Gurus,

I am trying to prototype a set up based on an SAP how to doc (updated by SAP in Nov 2007), which is a doc on configuring a delta load from the totals cube to a basic cube.

Please note that this doc, doesnt talk about doing an export datasource from the virtual cube. It mentions about doing it directly out of the transaction cube.

Has anyone done this and set this scenario?

I have certain issues on it.

1. I am trying a full load from the totals cube to the basic cube. Just the latest request's data is being extracted and not the data, part of the older requests!

2. Do I need to extract based on a cons group ? Do I need to add any selections ? The how to doc mentions about an infopackage selection on cons group. But I dont know, if that is needed ? We will be having only one hierarchy on cons group?

3. Can I set up full loads always, without issues of performance?

4. And finally, has someone modified the function modules as mentioned in the document, to prevent the front end impact on the queries?

Thanks in advance,

Prakash