Skip to Content
0
Former Member
Jul 12, 2011 at 06:28 AM

Transformation: Need for calling a custom function module on source system

58 Views

Hi Gurus,

I need to use a custom FM residing on source system within the transformation to determine the type (e.g. posting type) of a document item. The logic is quite complex with many exceptions (many if statements) and 2 customizing & few transparent tables are in use as well in the FM.

From my point of view, there are few options for achieving the outcome:

1. Copy the FM logic 1:1 in transformation

2. Transport the FM from ERP to BW system

3. Source system delivers the info (e.g. with an extra field "posting_type")

4. Access the FM directly via RFC/BAPI

However, there are pros and cons for each of the alternatives:

*Option 1*
pros: 
cons: consistency problem, need for importing customizing tables & source tables, high maintenance effort

*Option 2* 
pros: better consistency compared to Option 1
cons: need for importing tables, administrative efforts

*Option 3*
pros: no logic is needed at BW side, no transformations means no impact on performance, high consistency, no administrative effort
cons: structure in source system has to be changed, impact on historical records

*Option 4*
pros: best consistency (better than Option 3 as FM might change), no administrative effort
cons: impact on performance during transformation

Could you please verify my assumptions and give suggestions on solving the problem?

Thanks a lot!

Regards,

Meng