public override void Action()
{
     string result = string.Empty;

     using (var connection = Session.Login.Database.OpenConnection(DatabaseType.Operational))
     {
            string tableQuery = "SELECT Kod FROM Towary ORDER BY CONVERT(SUBSTRING_INDEX(SUBSTR(Kod, 2),'-',-1),UNSIGNED INTEGER) DESC LIMIT 1";

          Devart.Data.MySql.MySqlDataReader tableResult = ( Devart.Data.MySql.MySqlDataReader)connection.ExecuteCommand(ExecuteMode.Reader, tableQuery);

            while (tableResult.Read())
            {
                 result = tableResult.GetString(0);
                 break;
            }

            tableResult.Close();
     }

     if(!string.IsNullOrEmpty(result))
     {
          result = (Convert.ToInt32(string.Join(string.Empty, result.Where(char.IsDigit))) + 1).ToString();
          Row.Kod = "M" + result;
     }

    Task.Delete();
}