django - 属性错误 : 'RelatedManager' object has no attribute 'remove'

Question

在我的代码中的某处说

publisher.publisherperson_set.remove(email__in=pp_remove_set)

执行此操作后，我得到了

AttributeError: 'RelatedManager' object has no attribute 'remove'

事实上:我看着 dir(publisher.publisherperson_set)它有很多操作(包括 add )，但没有 remove .

在什么情况下这是可能的？

Answer 1

不能是 null
documentation for RelatedManager.remove() 说

For ForeignKey objects, this method only exists if null=True. If the related field can’t be set to None (NULL), then an object can’t be removed from a relation without being added to another.

很明显，一旦你想到它。
我真正想做的是:

publisher.publisherperson_set.filter(email__in=pp_remove_set).delete()