DOCTRINE :: OneToOne关系在持久化时崩溃

getting deeper into doctrine. But actually I get stucked with this.

Got this to persist:

$f = new Field();
$f->setValue(123);
$em = $this->getEntityManager();
$em->persist($f);
$em->flush();

In my Entity called Field I will relate to an Entity called Integer

/**
 * @ORM\OneToOne(targetEntity="Integer", mappedBy="field", cascade="persist") 
 **/
private $integer;

In my Entity Integer I need to relate to Field like this
/**
 * @ORM\OneToOne(targetEntity="Field", inversedBy="integer")
 * @ORM\JoinColumn(name="fid", referencedColumnName="id")
 **/
private $field;

it works, but how can I read the integer? I can see the field ID in the integer table for the new entry. But shouldn't be there a column in Fields pointing to integers?

I tried to set a column for relating to integers in fields entity like this:

* @ORM\JoinColumn(name="int", referencedColumnName="id")

But it did not work

cu n00n