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copied!<p>If the data you wish to access is an attribute on the join table, then includes is a pretty clean way to do it.</p> <p>However, from your post it seems like you have a method on the membership that wants to do some intelligent work with the underlying data. Also, it seems like you want to do two things with one query:</p> <ol> <li>Output user information (which is why you're iterating on the user object in the first place, if you just wanted memberships you'd just iterate on those).</li> <li>Output some intelligent and processed information for your membership object.</li> </ol> <p>As you've noticed, anything you do here feels weird because no matter where you put that code, it doesn't feel like the right model.</p> <p>I usually identify this feeling as the need for another abstraction layer. Consider creating a new model called MembershipUsers (it's a terrible name, but you can think of a different one).</p> <p>The following is my ad-hoc coding attempt that is untested but should give you an idea of the solution:</p> <pre class="lang-rb prettyprint-override"><code>class MembershipUser < User def self.for_group(group) select('memberships.*, users.*'). joins('join memberships on memberships.user_id = users.id'). where('memberships.group_id = ?', group.id) end def foo # now you have access to the user attributes and membership attributes # and you are free to use both sets of data for your processing end end </code></pre> <p>By creating a class that represents the User and their Membership to a specified Group, you've created a context where the foo method feels appropriate. I'm guessing that foo didn't mean much without being in the context of a specific user, and that you references the associated user in the foo method.</p> <p>-Nick (@ngauthier)</p> <p>EDIT: forgot to bring this full-circle:</p> <pre><code>class Group def membership_users MembershipUser.for_group(self) end end # then iterate group.membership_users.each do |membership_user| membership_user.user_name # a pretend method on user model membership_user.foo # the foo method that's only on MembershipUser end </code></pre>

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