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POIs it possible to get the ActiveRecord::Relation object for an association
 

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    <ol> <li><p>Do association methods, such as those defined by <code>has_many</code> and <code>belongs_to</code> utilize <code>ActiveRecord::Relation</code>?</p></li> <li><p>If so, is it possible to get the <code>ActiveRecord::Relation</code> object that is being used.</p></li> </ol> <p>We're all aware that Rails 3 is heavily using <code>ActiveRecord::Relation</code> objects, and <code>Arel::Relation</code> objects in the background, when creating queries using the <a href="http://edgeguides.rubyonrails.org/active_record_querying.html#retrieving-objects-from-the-database" rel="noreferrer">Query Interface</a>. Whenever we use the <code>select</code>, <code>joins</code>, etc. methods of the Query Interface, a <code>ActiveRecord::Relation</code> object is returned. However, this doesn't seem to be the case when calling an association method of a model. Instead, the query is executed immediately and an instance, or an array of instances, of the associated model is returned.</p> <p>Consider the following models:</p> <p><code>post.rb</code></p> <pre><code>class Post &lt; ActiveRecord::Base belongs_to :user end </code></pre> <p><code>user.rb</code></p> <pre><code>class user &lt; ActiveRecord::Base has_many :posts end </code></pre> <p>Example:</p> <pre><code>u = User.first u.posts </code></pre> <p>Calling <code>u.posts</code> returns an array of posts, not an instance of <code>ActiveRecord::Relation</code>. I'm wondering if it's possible to get the <code>ActiveRecord::Relation</code> that is <em>being used by the association</em>, if it is being used at all, perhaps by using <code>Arel::Table</code>?</p> <p>My reasoning for wanting the <code>ActiveRecord::Relation</code> should be obvious: It is because I want to chain off the existing association and manipulate the query to suit a different purpose.</p>
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