title: What type of NoSQL database is best suited to store hierarchical data?
body: <p>What type of NoSQL database is best suited to store hierarchical data?</p>
  
  <p>Say for example I want to store posts of a forum with a tree structure:</p>
  
  <pre><code>original post
   + re: original post
   + re: original post
     + re2: original post
       + re3: original post
     + re2: original post
  </code></pre>