title: How redis work?
body: <p>I am studying Redis, and I surprise how Redis works. I found that Redis, store recent data in cache in NoSQL format and have their own query for that. But I am curious about the following working:</p>
  
  <ol>
  <li><p>How data store in persistence database. Do we need to fire same insert query in both the database?</p></li>
  <li><p>If Redis uses NoSQL database is it compulsory that persistence database we are using is follow NoSQL structure?  </p></li>
  <li>How data synchronisation works between Redis database and persistence database?</li>
  </ol>