Django Querying Relation of Relation

Posted by Brent on Stack Overflow See other posts from Stack Overflow or by Brent
Published on 2012-09-13T19:20:09Z Indexed on 2012/09/13 21:38 UTC
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django

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orm

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django-models

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django-orm

I'm stuck on a Django ORM issue that is bugging me. I have a set of models linked by a foreign key but the requirements are a bit odd. I need to list items by their relation's relation. This is hard to explain so I've tried to depict this below, given:

Work

ManyToMany(Award)

Award

ForeignKey(AwardCategory)

AwardCategory

I need to list work items so they are listed by the award category. Desired output would be:

Work Instance A

Award Instance A that belongs to Award Category Instance A
Award Instance C that belongs to Award Category Instance A
Award Instance G that belongs to Award Category Instance A

Work Instance A (same instance as above, but listed by different award__category)

Award Instance F that belongs to Award Category Instance B
Award Instance R that belongs to Award Category Instance B
Award Instance Z that belongs to Award Category Instance B

Work Instance B

Award Instance B that belongs to Award Category Instance A
Award Instance A that belongs to Award Category Instance A

Essentially I want to list all work by the award category. I can get this to work in part but my solution is filthy and gross. I'm wondering if there is a better way. I considered using a ManyToMany and a through attribute but I'm not certain if I'm utilizing it correctly.

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