title: Nested Join vs Merge Join vs Hash Join in PostgreSQL
body: <p>I know how the </p>
  
  <ol>
  <li>Nested Join</li>
  <li>Merge Join</li>
  <li>Hash Join  </li>
  </ol>
  
  <p>works and its functionality. </p>
  
  <p>I wanted to know in which situation these joins are used in Postgres </p>