title: Rails can't write to serialized array field in database
body: <p>I have the array on my model and set up, and when I go to write the array onto my record it says COMMIT true, yet checking the field on that record immediately after returns an empty array.</p>
  
  <p>Model:</p>
  
  <pre><code>class Feature &lt; ActiveRecord::Base
    serialize :content, Array
    attr_accessible :content
  end
  </code></pre>
  
  <p>Migration:</p>
  
  <pre><code>class AddContentToFeatures &lt; ActiveRecord::Migration
    def change
      add_column :features, :content, :text, array: true, default: []
    end
  end
  </code></pre>
  
  <p>What I tried, along with various symbol and string syntaxes, is this:</p>
  
  <pre><code>&gt; f=Feature.new
  &gt; f.content_will_change! #i feel like i shouldn't have to do this
  &gt; f.content = ['sadasd','asdasd']
  &gt; f.save!
      BEGIN
      COMMIT
  =&gt; true
  &gt; f.content
  =&gt; []
  </code></pre>
  
  <p>How do I persist the array on the model?</p>