如上所述，我已经添加了=EAGER属性到关系注释，现在一切似乎都很好（除了加载不再懒惰的事实）。

这当然是解决方法，而不是修复实际的错误。除此之外，我还不知道是什么导致我的代码/原则打破。然而，这种解决方法的性能影响似乎是可以忽略的 - 如果甚至出现在这里。

I'm using PHP and Doctrine 2.0. All entities work fine, with the exception of the entity-relation detailed below (or other entities are failing where I'm not noticing it).

Consider the following entities:

/** @Entity */
class Target {
  /**
   * @ManyToOne(targetEntity="k\entity\Source", cascade={"persist"})
   * @JoinColumn(name="basic_vacancy_id", nullable=false)
   * @var \k\entity\Source
   */
  $source;

  ...
}

/** @Entity */
class Source {

  ...
}

Now, when I call $target->getSource() I get an instance of k\entity\proxy\kentitySourceProxy (which is the correct proxy class). However, all the getters for Source's properties return NULL.

What could I be doing wrong?

I've added the fetch="EAGER" attribute to the relational annotation, and now everything seems to go just fine (except for the fact that loading is no longer lazy). What could cause Doctrine 2.0's lazy loading to break?

As seen above in my question, I've added the fetch="EAGER" attribute to the relational annotation, and now everything seems to go just fine (except for the fact that loading is no longer lazy).

This is of course a workaround, and no fix of the actual bug. In addition to this, I still don't know what caused my code/Doctrine to break. However, the performance impact of this workaround seems to be negligible - if even present at all.