Select the Fields you need to download and to convert.
Click that the incremental field is an update field and select the Field. Tell the Wilcon DWH Builder which value has to be read and which value will be the Update value.
In this case you tell Wilcon DWH Builder to read all records with the condition PROCESS_FLAG = N.
Each processed record WILCON DWH Builder will be updated to PROCESS_FLAG = Y so that the next time this record will not be read anymore.