PHP PDO 事务?

I thinks it's best I show my code; I have commented out the code and have explained in the code which may make it easier to understand.

// Begin our transaction, we need to insert data into 4 tables:
// users, users_status, users_roles, users_profiles
// connect to database
$dbh = sql_con();

// begin transaction
$dbh->beginTransaction();

try {

    // this query inserts data into the `users` table
    $stmt = $dbh->prepare('
                        INSERT INTO `users`
                        (users_status, user_login, user_pass, user_email, user_registered)
                        VALUES
                        (?, ?, ?, ?, NOW())');

    $stmt->bindParam(1, $userstatus,     PDO::PARAM_STR);
    $stmt->bindParam(2, $username,       PDO::PARAM_STR);
    $stmt->bindParam(3, $HashedPassword, PDO::PARAM_STR);
    $stmt->bindParam(4, $email,          PDO::PARAM_STR);
    $stmt->execute();

    // get user_uid from insert for use in other tables below
    $lastInsertID = $dbh->lastInsertId();

    // this query inserts data into the `users_status` table
    $stmt = $dbh->prepare('
                        INSERT INTO `users_status`
                        (user_uid, user_activation_key)
                        VALUES
                        (?, ?)');

    $stmt->bindParam(1, $lastInsertID,     PDO::PARAM_STR);
    $stmt->bindParam(2, $activationkey,    PDO::PARAM_STR);
    $stmt->execute();

    // this query inserts data into the `users_roles` table
    $stmt = $dbh->prepare('
                        INSERT INTO `users_roles`
                        (user_uid, user_role)
                        VALUES
                        (?, ?)');

    $stmt->bindParam(1, $lastInsertID,      PDO::PARAM_STR);
    $stmt->bindParam(2, SUBSCRIBER_ROLE,    PDO::PARAM_STR);
    $stmt->execute();

    // this query inserts data into the `users_profiles` table
    $stmt = $dbh->prepare('
                        INSERT INTO `users_profiles`
                        (user_uid)
                        VALUES
                        (?)');

    $stmt->bindParam(1, $lastInsertID,      PDO::PARAM_STR);
    $stmt->execute();

    // commit transaction
    $dbh->commit();

} // any errors from the above database queries will be catched
catch (PDOException $e) {
    // roll back transaction
    $dbh->rollback();
    // log any errors to file
    ExceptionErrorHandler($e);
    require_once($footer_inc);
    exit;
}

我是 PDO 的新手，上面可能存在我尚未注意到的错误或问题，因为在找出问题之前我无法进行测试.