问如何处理PDO异常？

<?php
// $connection alreay created on a class which works with similar UPDATE statements
// I've simply added here trim() and PDO::PARAM... data type


$id = 33;
$name = "Mario Bros.";
$url = "http://nintendo.com";
$country = "jp";


try {

$sql = "UPDATE table_users SET name = :name, url = :url, country = :country WHERE user_id = :user_id";

$statement = $connection->prepare ($sql);

$statement->bindParam (':user_id', trim($id), PDO::PARAM_INT);
$statement->bindParam (':name', trim($name), PDO::PARAM_STR);
$statement->bindParam (':url', trim($url), PDO::PARAM_STR);
$statement->bindParam (':country', trim($country), PDO::PARAM_STR, 2);

$status = $statement->execute ();

} catch (PDOException $e) {
    print $e->getMessage ();
}

print $status; // it returns a null value, and no errors are reported

?>