Merging flows

Hi,

We want to combine the data. What are my options? BW 7.4.

Any other way other than creating a consolidation DSO on the top and writing code to handle delta in transformation routines, then taking care of data integrity using function module ?

Please note any change to any document from all 3 flows should be captured everytime in the consolidated DSO.

Left Outer join in a composite provider perhaps? but only the left gets taken care in that case.

Regards,

Cleo