title: Scaling Postgres horizontally
body: <p>Let we say you are running your business on top of postgresql database. After some time you get so much traffic that it cannot be handled by single postgresql instance, so you want to add more instances (scale it horizontally) to be able to handle growth.</p>
  
  <p>Your data is relational, so probably switching to some key/value solution is not an option.</p>
  
  <p>How would you do it with postgresql? </p>
  
  <p>PS. Postgresql version: 9.5 </p>