From: David Heinemeier Hansson <david@...>
Date: 2004-09-27T23:52:55+09:00
Subject: Re: [Rails] #has_and_belongs_to_many problem

Try this instead:

class Permission < ActiveRecord::Base
   has_and_belongs_to_many :roles

   protected
     def before_destroy
       connection.delete(
         "DELETE * FROM permissions_roles WHERE permission_id = #{id}"
       )
     end
end

Some times a little SQL is just what you need. Active Record doesn't 
look down upon you for doing that. Unlike many other frameworks.

I'll get a :dependent => true option in at some point that'll do this 
automatically, though.

Oh, and thanks for the praise! I'm glad you're having fun and are being 
productive.
--
David Heinemeier Hansson,
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