SRM 7.0 Modify POWL for shopping cart ->Additional Field PR

Hello,

in standard POWL for Shopping Cart it is possible to filter Carts with "Order No. from ERP".

Now we need also to add a new search field for "Purchase Requisition", that the user has both possibilites to filter for backend follow-up documents.

How could this been done?

Do we need to copy and change the feeder class for this or can is be done via Customizing?

I think the problem is, that in table BBP_PDBEI there is only one column for backend-document number (BE_OBJECT_ID) and next to is there is a column that defines the BUS Type, e.g. order or PR.

Do we need to adjust the feeder class to look in this table for the BE_OBJECT_ID with "BUS2105"?

Thanks for your help!

Regards Trevor