Complicted ActiveRecord Association. Going through a 4th table

Posted by Dex on Stack Overflow See other posts from Stack Overflow or by Dex
Published on 2010-04-22T00:29:31Z Indexed on 2010/04/22 0:33 UTC
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ruby-on-rails

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activerecord

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associations

I have kind of a complicated case and am wondering how this would work in rails:

I want to categories the genres of some singers. Singers can belong to more than one genres, and users can assign tags to each genre

For example: singers <-- singers_genres --> genres <-- genres_tags --> tags

SQL would look something like: SELECT * FROM singers S INNER JOIN singers_genres SG ON S.id=SG.singer_id INNER JOIN genres G ON G.id = SG.genre_id LEFT OUTER JOIN genre_tags GT ON G.id = GT.genre_id INNER JOIN tags T ON GT.tag_id = T.id

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