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Date: Thu, 28 Oct 2010 09:02:50 -0500
Message-ID: <AANLkTimh6-MpMxMNt0kDQ5hPkfMzxZKzsaUMTNnYK6kz@mail.gmail.com>
Subject: Re: Feature request: ForeignKey through parameter
From: Javier Guerra Giraldez <jav...@guerrag.com>
To: django-developers@googlegroups.com
Cc: Roald de Vries <ro...@go2people.nl>
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On Thu, Oct 28, 2010 at 2:54 AM, Roald de Vries <downa...@gmail.com> wrote:
> I quite often reference foreign keys of foreign keys of foreign keys...
> Wouldn't it be nice to have a 'through'-parameter for ForeignKey's?
>
>
> =C2=A0 =C2=A0class A(Model):
> =C2=A0 =C2=A0 =C2=A0 =C2=A0b =3D ForeignKey('B')
> =C2=A0 =C2=A0 =C2=A0 =C2=A0c =3D ForeignKey('C', through=3D'B', related_n=
ame=3D'a_set')
>
> =C2=A0 =C2=A0class B(Model):
> =C2=A0 =C2=A0 =C2=A0 =C2=A0c =3D ForeignKey('C')

i'd love such a feature too, but i think a better syntax could be
something like:

   class A(Model):
       b =3D ForeignKey('B')
       c =3D ForeignKey('B__c', related_name=3D'a_set')

   class B(Model):
       c =3D ForeignKey('C')

where the second part of the reference is the name of the field ('c'
in this example), not the model class ('C')

--=20
Javier