title: Use of natural key in date dimension
body: <p>I am trying really hard to understand the concept of having natural keys in date Dimension table. </p>
  
  <p>I have always seen a random surrogate keys being created in the dimension tables. But I have recently read that using a natural key in date dimension something like <code>20150806</code> for <code>Aug-06-2015</code> works much better and has considerable performance gain when it comes to lookup and reverse lookup from 
  fact tables when compared with a natural surrogate key which is <code>int</code> by nature.</p>
  
  <p>I can't understand how it will give any performance gain. We still would require <code>join</code> between facts and dimension even if we use this fancy key for date dimension. </p>
  
  <p>If anyone has any insight on this, would you please mind sharing the knowledge. I would appreciate if you could follow up with an example.</p>