protected void btnUpdate_Click(object sender, EventArgs e)
        {
            DBOps db = new DBOps();

            string _key   = txtKey.Text;
            long   _value = long.Parse(txtValue.Text);

            int retval = db.UpdateItemsTable(_key, _value);

            lblUpdateInfo.Text = retval.ToString() + " rows updated";
            lblUpdateInfo.DataBind();

            RefreshTable();
        }