Filter through a related model django

How can 开发者_高级运维I generate a query_set through a related model?

For example, how can I do this:

UserProfile.objects.filter(user.is_active=True) # Can't use user.is_active to filter

Trivial question, trivial answer. But I'll keep it here for posterity's sake.

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UserProfile.objects.filter(user__is_active=True) 

This is well documented in the Django docs.

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From the Django documention

Django offers a powerful and intuitive way to "follow" relationships in lookups, taking care of the SQL JOINs for you automatically, behind the scenes. To span a relationship, just use the field name of related fields across models, separated by double underscores, until you get to the field you want.

In your example this would be:

 UserProfile.objects.filter(user__is_active=True)

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The easiest way to follow a relationship is to use a simple "__".

UserProfile.objects.filter(user__is_active=True)

These can be changed together as well (ie user_parent_email='abc@def.com')