kden

$result = $conpdo->prepare("SELECT * FROM `logs` WHERE `username` LIKE :username");
$result->execute(array(':username' => $_GET['username']));
$info = $result->fetch(PDO::FETCH_ASSOC);

if(empty($info))
{
    $result = $conpdo->prepare("INSERT INTO `logs` (`id`, `ip`, `username`, `last_update`) VALUES (NULL, :ip, :username, '0000-00-00 00:00:00');");
    $result->execute(array(':username' => $_GET['username'], ':ip' => $_GET['ip']));
}
else
{
    $result = $conpdo->prepare("UPDATE `logs` SET `ip` = :ip WHERE `logs`.`id` = :id");
    $result->execute(array(':ip' => $_GET['ip'], ':id' => $info['id']));
}