Yeah, sorry about that. Well the file will only contain changes that need to be reflected in the old file (which servers as a master). Usually the file contains around 120 fields which then need to be updated. Besides that I will need to update around 150 other fields that serves as descriptions of the original fields.
After that there is some appends of data to be done which usually is a couple of million rows.
After that there is some appends of data to be done which usually is a couple of million rows.