对于django-model-utils，如何将select_subclasses()应用于对象的字段? [英] For django-model-utils, how can `select_subclasses()` be applied to fields of an object?

问题描述

我有一些这样的模型:

class Container(models.Model):
    pass

class Parent(models.Model):
    container = models.ForeignKey(Container, related_name='items')
    pass

class Child(Parent):
    pass

class RedHeadedStepChild(Parent):
    pass

是否可以使用 select_subclasses()来预取容器中的字段?我想做这样的事情:

Is it possible to use select_subclasses() to prefetch fields in the container? I want to do something like this:

qs = Container.objects.all().prefetch_related('items')\
     .select_subclasses() # <---

因此，每个 Container 的 items 相关字段都可以在其各自的子类类型中进行检索.

So that the items related field of each Container is retrieved in each of its respective subclass types.

推荐答案

有关:

Container.objects.prefetch_related(
    Prefetch('items', Parent.objects.select_subclasses())
)

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