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copied!<p>I believe you will need at least two AR query invocations (as you currently have) because of the <code>limit(20)</code> clause. Your queries currently gives you up to 20 Posts, AND up to 20 Projects, so doing an aggregate limit on both activity types in a single query would not give the intended result.</p> <p>I think all you need to do is use <code>eager_load</code> in the query instead of <code>includes</code> to force a single query. The differences between <code>joins</code>, <code>includes</code>, <code>preload</code>, <code>eager_load</code> and <code>references</code> methods are nicely covered <a href="http://blog.bigbinary.com/2013/07/01/preload-vs-eager-load-vs-joins-vs-includes.html" rel="nofollow">here</a></p> <p>So, with AR and squeel:</p> <pre><code>def index @activities = Activity.limit(20).order { created_at.desc } @one = @activities.where{trackable_type == 'Post'}.eager_loads(trackable: [:author, :project]) @two = @activities.where{trackable_type == 'Project'}.eager_loads trackable: [:owner] @activities = @one + @two end </code></pre> <p>And without the squeel, using just regular ActiveRecord 4:</p> <pre><code>def index @activities = Activity.limit(20).order(created_at: :desc) @one = @activities.where(trackable_type: 'Post').eager_loads(trackable: [:author, :project]) @two = @activities.where(trackable_type: 'Project').eager_loads(trackable: :owner) @activities = @one + @two end </code></pre> <p>You don't need squeel, I recently ripped it out of my project because it doesn't work properly for a number of complex queries in my experience, where AR 4 and Arel were ok.</p>

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