public Reservation CreateReservation(Place place, Customer customer, List <Guest> guests, DateTime start, DateTime end) { parameters.Add("@customerId", customer.Id); parameters.Add("@placeId", place.Id); parameters.Add("@startDate", start.ToString("MM-dd-yyyy HH:mm:ss")); parameters.Add("@endDate", end.ToString("MM-dd-yyyy HH:mm:ss")); List <object> row = this.QueryRow(@" INSERT INTO reservation(customerId, placeId, startDate, endDate) OUTPUT INSERTED.* VALUES(@customerId, @placeId, @startDate, @endDate) "); Reservation reservation = this.GetReservationFromSqlRow(row); foreach (Guest guest in guests) { reservation.AddGuest(guest); } return(reservation); }