Change logs for primary key's in DSO

Dear Experts

We have requirement like we need to load the data from KNVP table for only primary keys in the same table. We have around 6 fields.and i have maintained all these fields in key fields tab in standard DSO.. When i ran delta changes are not overwritten. RECORD MODE showing as "N" for all records (full + delta). But we have to overwrite the change/inserted fields. Kindly please let me know how to achieve this scenario

Thanks in Advance.