How to design model for multi-tiered data?

Posted by Chris on Stack Overflow See other posts from Stack Overflow or by Chris
Published on 2010-05-01T09:40:29Z Indexed on 2010/05/01 9:47 UTC
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database-design

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django

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django-models

Say I have three types of object: Area, Subarea and Topic. I want to be able to display an Area, which is just a list of Subareas and the Topics contained in those Subareas. I never want to be able to display Subareas separately - they're just for breaking up the Topics. Topics can, however, appear in multiple Areas (but probably under the same Subarea).

How would I design a model for this? I could use ForeignKey from Topic to Subarea and from Subarea to Area, but it seems unnecessarily complex given that I never want to interact with subareas themselves.

Also, none of these objects are ever altered or added to by the user. They're just for me to represent information. Maybe there is a better way to represent it all?

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