DataTable dt = SqlHelper.ExecuteDataTable(parameter )

if (dt.Rows.Count <= )

            {

                return null;

            }

            else if (dt.Rows.Count > )

            {

                throw new Exception("More than one data");

            }

            else

            {

                DataRow row = dt.Rows[];

                Customer cust = new Customer();

                cust.Id = (long)row["id"];

                cust.Name = (string)row["Name"];

                cust.BirthDay =

                    (DateTime?)SqlHelper.FromDbValue(row["BirthDay"]);

                cust.Address = (string)row["address"];

                cust.CustLevel = (int)row["CustLevel"];

                cust.TelNum = (string)row["TelNum"];

                return cust;

            }