title: How do you tell Mongo to sort a collection before limiting the results?
body: <p>I want to select the most recent documents from a collection.  The answer from this question <a href="https://stackoverflow.com/questions/4421207/mongodb-how-to-get-the-last-n-records">mongodb: how to get the last N records?</a> suggests that the order of operations in the query matters.  However this does not appear to be the case (perhaps since Mongo 2.4 was released).  I've tried both of the following queries and it appears that Mongo first applies the limit and then performs the sort.  </p>
  
  <p>Query 1</p>
  
  <pre><code>myCollection.find().sort( { '$date': 1 }).limit(50, callback);
  </code></pre>
  
  <p>Query 2</p>
  
  <pre><code>myCollection.find().limit(50).sort( { '$date': 1 }, callback);
  </code></pre>
  
  <p>What would be the correct query to tell mongo to sort first and limit second?</p>
  
  <p>EDIT --- Here's a sample document from the collection</p>
  
  <pre><code>{
    _id: ObjectId("517eb0dddbab79c74700005d"),
    audioFiles: [
      {
        audioFileName: "C64FEFA8-DD43-40A1-8996-35948F3438BF-6896-0000027BD4A59D91",
        audioLanguage: "English",
        date: ISODate("2013-05-21T16:23:04.006Z"),
        flag: "1",
        user: "36C4DEB6-C13D-4211-94B5-CC4DD993ECF1-6896-00000278FA7B08EC"
      },
      {
        audioFileName: "994B6DF6-73B5-458F-912A-FF67A84534B2-23532-0000020000000000",
        audioLanguage: "English",
        date: ISODate("2013-05-27T10:45:04.107Z"),
        flag: "1",
        user: "9D7BB3F4-371B-4F2A-8DA2-0C4CE8B4E16D-974-0000000000000000"
      }
    ],
    date: ISODate("2013-04-29T17:41:49.101Z"),
    imageFileName: "SteamLokomotive0498",
    random: 0.6750695831142366,
    thumbFileName: "SteamLokomotive0498_150x150",
    user: "62923D8E-00CE-4F0C-AECA-3010D78FC9CE-226-0000000000000000",
    userLanguagePref: "Cantonese"
  }
  </code></pre>