title: MongoDB: Get latest 10 items in different data model?
body: <p>I'm trying to do a personal blog system with MongoDB. The blog system designed to support both formal article and short tweets, which have similar but different data structures. For example, an article must have a title, but tweets must not; both them have a creation date.</p>
  
  <p>There is also a timeline feature in design. The timeline will show latest 10 items, no matter the item is an article or a tweet, and when "load more" button pressed, there will show the 10-20 items...</p>
  
  <p>So I think there are two method to design the database schema</p>
  
  <ol>
  <li>Save articles and tweets into separate collections.</li>
  <li>Save all things into a single collection, add a "type" field for specifying.</li>
  </ol>
  
  <p>And I have three questions:</p>
  
  <ol>
  <li>If I use method 1, how to implement the "latest 10 items" query?  Any literal explanation, or example code in MongoDB query language, mongoose, mongoengine or else, is welcome.</li>
  <li>If I use traditional SQL DB (like MySQL), is there a common method to solve the "latest 10 items" problem ?</li>
  <li>Which methods fits the MongoDB's philosophy more ?</li>
  </ol>
  
  <p>Thanks</p>