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POWhen to use Embedded Documents?
 

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    <p>I am trying to figure out how to layout my database for a site I am working on. Here are my models:</p> <pre><code>class User include MongoMapper::Document // keys here many :items many :likes end class Item include MongoMapper::Document key :name, String, :required =&gt; true many :likes end class Like include MongoMapper::EmbeddedDocument key :user_id, String, :required =&gt; true end </code></pre> <p>I believe the <code>Like</code> should be embedded somewhere, but I am having a hard time picking one because of the functionality I would like to get out of it.</p> <pre><code>user = User.first user.likes // should print out all the Items he liked item = Item.first item.likes // so I can count how many people like that item </code></pre> <p>Although the problem comes when using an EmbeddedDocument, you lose the <code>find</code>, and other helpful methods, and you can't have it embedded in both models. So having it only in <code>Item</code>, I would need to run this (but can't):</p> <pre><code>item = Item.first item.likes.find_by_user_id(User.first._id) </code></pre> <p>undefined method <code>find_by_user_id</code> will be thrown. So if I was to embed this into my <code>User</code>, I still couldn't do this.</p> <pre><code>likes = Like.all // will throw undefined `all` </code></pre> <p>So I came to the conclusing to maybe do it this way:</p> <pre><code>class Like include MongoMapper::Document key :user_id, String, :required =&gt; true key :item_id, String, :required =&gt; true belongs_to :user belongs_to :item end </code></pre> <p>But this seems like I am still trying to do things the old MySQL way. Could anybody give me a point on the most likely way to code this with MongoMapper?</p> <p>Thanks in advance!</p>
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