title: Is there performance difference between concat vs || in oracle
body: <p>I want to concat multiple(3) columns in oracle sql query. Currently I am using function <code>concat</code>. 
  Someone suggested to use <code>||</code> in place of <code>concat</code> as it gives performance benefit. </p>
  
  <p>Is it true? If yes why?</p>
  
  <p>I see only benefit of || is that written query more readable. </p>