public bool DeleteCoupons(Coupon oldCoupon)
 {
     try
     {
         DataContext.Coupon.DeleteOnSubmit(oldCoupon);
         DataContext.SubmitChanges();
         return true;
     }
     catch (Exception) /*FIXME*/
     {
         return false;
     }
 }
 partial void DeleteCoupon(Coupon instance);
 partial void UpdateCoupon(Coupon instance);
 partial void InsertCoupon(Coupon instance);
 public bool InsertCoupons(Coupon newCoupon)
 {
     try
     {
         DataContext.Coupon.InsertOnSubmit(newCoupon);
         DataContext.SubmitChanges();
         return true;
     }
     catch (Exception) /*FIXME*/
     {
         return false;
     }
 }
 public bool EditCoupons(decimal oldValue, Coupon newCoupon)
 {
     try
     {
         Coupon editableCoupon = DataContext.Coupon.Single(c => c.Value == oldValue);
         editableCoupon.Value = newCoupon.Value;
         editableCoupon.StartDate = newCoupon.StartDate;
         editableCoupon.LastDate = newCoupon.LastDate;
         editableCoupon.Frequency = newCoupon.Frequency;
         DataContext.SubmitChanges();
         return true;
     }
     catch (Exception) /*FIXME*/
     {
         return false;
     }
 }