function __calc_used_money($facebook)
{
    $President = new President();
    $condition = array('facebook_id' => $facebook->getUser());
    $me = $President->findBy($condition)->fetch_assoc();
    if ($me['used_money'] > 0) {
        $now = time();
        $updated_at = $me['updated_at'];
        // 回復量を計算
        $recover = ($now - $updated_at) * RECOVER_RATE;
        $used_money = $me['used_money'] - $recover;
        if ($used_money < 0) {
            $used_money = 0;
        }
        $data = array('used_money' => $used_money, 'updated_at' => $now);
        $President->update($data, $condition);
    }
}
<?php

require dirname(__FILE__) . '/../../model/President.php';
$Model = new President();
$data = array('princess_id' => '10');
$condition = array('facebook_id' => '1203983052');
echo $Model->update($data, $condition) . "\n<br />";
var_dump($insertData);
<?php

require dirname(__FILE__) . '/../facebook.php';
require dirname(__FILE__) . '/../model/President.php';
$facebook_id = $facebook->getUser();
$Model = new President();
$data = array('princess_id' => $_GET['princess_id']);
$condition = array('facebook_id' => $facebook_id);
$result = $Model->update($data, $condition);
// リダイレクト
header("HTTP/1.1 301 Moved Permanently");
header("Location: /president/index.php");