Rails 2.3: How to create this SQL into a named_scope

Posted by randombits on Stack Overflow See other posts from Stack Overflow or by randombits
Published on 2010-05-30T04:28:45Z Indexed on 2010/05/30 4:32 UTC
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ruby-on-rails

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ruby

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activerecord

Having a bit of difficulty figuring out how to create a named_scope from this SQL query:

select * from foo where id NOT IN (select foo_id from bar) AND foo.category = ? ORDER BY RAND() LIMIT 1;

Category should be variable to change.

What's the most efficient way the named_scope can be written for the problem above?

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