我可以将Doctrine事务与mysql PDO语句一起使用吗？

Question

从下面的代码中我预计$ query1将在Exception之后撤消 抛出。但事实并非如此。

try {
    $this->em->getConnection()->beginTransaction();
    PDO::exec($query1 = 'INSERT INTO foo...')
    throw new Exception();
    PDO::exec($query2 = 'INSERT INTO bar...')
    $this->em->flush();
    $this->em->getConnection()->commit();
} catch (\Exception $e) {
    $this->em->getConnection()->rollBack();
    throw $e;
}