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PORails Polymorphic Association with multiple associations on the same model
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copied!<p>My question is essentially the same as this one: <a href="https://stackoverflow.com/questions/1168047/polymorphic-association-with-multiple-associations-on-the-same-model">Polymorphic Association with multiple associations on the same model</a></p> <p>However, the proposed/accepted solution does not work, as illustrated by a commenter later.</p> <p>I have a Photo class that is used all over my app. A post can have a single photo. However, I want to re-use the polymorphic relationship to add a secondary photo.</p> <p>Before:</p> <pre><code>class Photo belongs_to :attachable, :polymorphic => true end class Post has_one :photo, :as => :attachable, :dependent => :destroy end </code></pre> <p>Desired:</p> <pre><code>class Photo belongs_to :attachable, :polymorphic => true end class Post has_one :photo, :as => :attachable, :dependent => :destroy has_one :secondary_photo, :as => :attachable, :dependent => :destroy end </code></pre> <p>However, this fails as it cannot find the class "SecondaryPhoto". Based on what I could tell from that other thread, I'd want to do:</p> <pre><code> has_one :secondary_photo, :as => :attachable, :class_name => "Photo", :dependent => :destroy </code></pre> <p>Except calling Post#secondary_photo simply returns the same photo that is attached via the Photo association, e.g. Post#photo === Post#secondary_photo. Looking at the SQL, it does WHERE type = "Photo" instead of, say, "SecondaryPhoto" as I'd like...</p> <p>Thoughts? Thanks!</p>

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