Django - 使用子对象过滤查询集(外键)

Question

我有 3 个模型，其中 2 个对应于第一个。

class Parent(models.Model):
    name = models.CharField....
    ...

class Child1(models.Model):
   parent = models.ForeignKey(Parent)
   ...

class Child2(models.Model):
   parent = models.ForeignKey(Parent)
   ...

现在，在我看来，我有 2 个过滤的查询集 Child1和 Child2对象。

有没有办法检索所有 Parent过滤查询集中的对象？

就像是...

children1 = Child1.objects.filter(blah=blah)
children2 = Child2.objects.filter(blah=blah)
parents = Parent.objects.filter(self__in=children1 or self__in=children2)

注意 上面的代码根本不起作用，这只是想法。

Answer 1

是的:

from django.db.models import Q

children1 = Child1.objects.filter(blah=blah)
children2 = Child2.objects.filter(blah=blah)
parents = Parent.objects.filter(Q(child1__in=children1) | Q(child2__in=children2))

见文档:

https://docs.djangoproject.com/en/1.7/ref/models/querysets/#in

https://docs.djangoproject.com/en/1.7/topics/db/queries/#lookups-that-span-relationships

https://docs.djangoproject.com/en/1.7/topics/db/queries/#complex-lookups-with-q-objects