private void UpdateDatabase()
        {
            DB.Open();
            DB.BeginTransaction();
            try
            {
                EmployeeAdd employeeAdd = new EmployeeAdd(employeesAddTDS);
                int employeeId = employeeAdd.Save();

                EmployeeAddTypeHistory employeeAddTypeHistory = new EmployeeAddTypeHistory(employeesAddTDS);
                employeeAddTypeHistory.Save(employeeId);
                hdfEmployeeId.Value = employeeId.ToString();

                DB.CommitTransaction();

                // Store datasets
                employeesAddTDS.AcceptChanges();
                Session["employeesAddTDS"] = employeesAddTDS;

            }
            catch (Exception ex)
            {
                DB.RollbackTransaction();

                string url = string.Format("./../../error_page.aspx?error={0}", ex.Message.Replace('\n', ' '));
                Response.Redirect(url);
            }
        }