title: Doctrine: How to store dynamic attributes
body: <p>I want to store dynamic attributes into the database.</p>
  
  <p>Example:
  Some user wants to create a profile with custom characteristics. This could be age, hobby, job, school or what else. Every user can set his own characteristic. On the server side this could look like:</p>
  
  <pre><code>    $characteristics = array(
          0 =&gt; array('age', 22),
          1 =&gt; array('hobby', 'php'),
          2 =&gt; array('food', 'pizza'),
      );
  </code></pre>
  
  <p>With this structure it is possible to read out the attribute itself and the value also I can easily add and remove attributes.</p>
  
  <p>Now I want to store such data by doctrine.</p>
  
  <p>The question is now how I do this best:</p>
  
  <ol>
  <li>Persist the Array</li>
  <li>JSON</li>
  <li>XML</li>
  <li>Other?</li>
  </ol>