DECLARE
   CURSOR cur_bill_customers
   IS
      SELECT *
        FROM apps.xxar_c110_custstg c110
       WHERE NVL (status, 'N') = 'N'
         AND site_use_code = 'BILL_TO';
BEGIN
   FOR cur_bill_customers_rec IN cur_bill_customers
   LOOP
      BEGIN
         UPDATE apps.xxar_c110_custstg
            SET orig_system_customer_ref =
                     'CUST' || cur_bill_customers_rec.orig_system_customer_ref,
                orig_system_address_ref =
                      'CUST'
                   || cur_bill_customers_rec.orig_system_customer_ref
                   || '_'
                   || 'ADRR'
                   || cur_bill_customers_rec.orig_system_address_ref
         WHERE  customer_number =
                               cur_bill_customers_rec.orig_system_customer_ref
            AND site_use_code = 'BILL_TO';
      END;
   END LOOP;
END;
/