title: Node JS Mongoose PULL query
body: <p>I find many great answers here on SO like <a href="https://stackoverflow.com/questions/19786075/mongoose-deleting-pull-a-document-within-an-array-does-not-work-with-objectid">this</a> answer an <a href="https://stackoverflow.com/questions/26405798/mongoose-pull-from-subdocument">this</a>. But i can not get it to work...
  I tried <code>ObjectId("55cf816559d2fc8d0e6c14a8")</code> in the query where the id is.</p>
  
  <p>This query works when robotmongo run it:</p>
  
  <pre><code>db.getCollection('events').update(
      { "_id": ObjectId("55cf816559d2fc8d0e6c14a8") }, 
      { "$pull": { "workers" : { "_id": ObjectId("55cf89ac7cba1d0a10ca86c7")}}},
      false,
      true
  )
  </code></pre>
  
  <p>Side note, what is the false,true for?</p>
  
  <p>Here is my current code</p>
  
  <pre><code>event.update(
      {'_id': "55cf816559d2fc8d0e6c14a8"}, 
      { "$pull": { "workers" : {_id: "55cf89ac7cba1d0a10ca86c7"}}},
      function(err, result) {
          console.log(err);
          console.log(result);
      }
  );
  </code></pre>
  
  <p>I do not get any errors and the result is equal to 1.</p>