django:从外键获取对象 [英] django : get object from foreign key

问题描述

假设遵循以下模型类，

 class Bookmark(models.Model):   
     owner = models.ForeignKey(UserProfile,related_name='bookmarkOwner')
     parent = models.ForeignKey(UserProfile,related_name='bookmarkParent')
     sitter = models.ForeignKey(UserProfile,related_name='bookmarkSitter')

我如何从 owner 对象中获取 sitter 对象?

How can I get sitter objects from owner Objects?

user = UserProfile.objects.get(pk=1)

UserProfile.objects.filter(bookmarkOwner=user)

返回空的 tuple ，我无法指定 sitter 变量.

returns empty tuple, and I cannot specify sitter variable.

推荐答案

如果您想避免使用循环，我相信您可以执行以下操作:

I believe you can do something like this, if you want to avoid using a loop:

pks = some_user_profile.bookmarkOwner.values_list('sitter', flat=True)
sitters = UserProfile.objects.filter(pk__in=pks).all()

或者，您可能想尝试设置多对多字段并使用 through 参数.请参阅Django文档: https://docs.djangoproject.com/en/2.0/ref/models/fields/#manytomanyfield

Alternatively, you might want to experiment with setting up a many-to-many field and using the through parameter. See the Django docs: https://docs.djangoproject.com/en/2.0/ref/models/fields/#manytomanyfield

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