Is there a way to have three way habtm associations in rails / activerecord?

Posted by txwikinger on Stack Overflow See other posts from Stack Overflow or by txwikinger
Published on 2010-05-10T18:29:23Z Indexed on 2010/05/10 18:34 UTC
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ruby-on-rails

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activerecord

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orm

Often three (or more) way associations are needed for habtm associations. For instance a permission model with roles.

A particular area of functionality has many users which can access many areas.

The permissions on the area are setup via roles (habtm)

The user/roles association is also habtm

The permissions (read, write, delete, etc) are habtm towards roles.

How would that be best done with rails/activerecord?

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