To add Custom fields in Standard Transaction MM01 in Basic Data 2 View and in Ware house Management 2 View.
* Add the Required fields custom fields in table using APPEND Structure .
For Basic Data 2 View – in MARA table
For Warehouse Management 2 View – in MLGN table
* Link the Custom screen with Standard screen in SPRO Transaction.
* Do the Changes in PBO and PBI events of the Function Group and in BADIs to modify the table MARA and MLGN with custom fields.
Please find the attached document for more information with the screen shot.
Thanks & Regards,