Update using Session

Question

Hi,     I am trying to update db using session, but unable to do  it..below is my code..redirect is working fine but I have added update on second page and to update using session but its not working ...


   string t = Session["s"].ToString();
                cn.Open();
                cmd.Connection = cn;
                cmd.CommandText = "Update Labtest_Table set Name='" + tbName.Text + "', Desgn='" + tbDesg.Text + "', Cata='" + tbCat.Text + "' where ID = @ID2";
            cmd.Parameters.AddWithValue("@ID2",t);  
            int row = cmd.ExecuteNonQuery();
                cn.Close();
                tbName.Text = "";
                tbDesg.Text = "";
                tbCat.Text = "";
         



plz help....