title: Efficient way to store and query tree-like hierarchical data
body: <p>Please see the image here:  </p>
  
  <p><a href="https://picasaweb.google.com/108987384888529766314/CS3217Project#5717590602842112850">https://picasaweb.google.com/108987384888529766314/CS3217Project#5717590602842112850</a></p>
  
  <p>So, as you can see from the image, we are trying to store hierarchical data into a database. 1 publisher has may articles, 1 article has many comments and so on. Thus, if I use a relational database like SQL Server, I will have a publisher table, then an articles table and a comments table. But the comments table will grow very quickly and become very large.</p>
  
  <p>Thus, is there any alternative which allows me to store and query such tree like data efficiently? How about NoSQL (MongoDB)?</p>