bulk user

I am in the process of adding a user points feature to a client's Drupal site.

Their plan is to award their customers points for each sales order, with the point amount calculated from the dollar amount of each order. All of their e-commerce is conducted on a separate (offline) intranet, with orders entered manually into a large db application.

I can get an Excel file output from their database, (easily converted to CSV) of all sales transactions, with points, user IDs, etc. A typical Excel file like this covers a single week's activity, and contains about 300 transactions.