title: mysql FIND_IN_SET equivalent to postgresql
body: <pre><code>select * 
  from folder f,uploads u 
  where u.id=f.folderId 
  and FIND_IN_SET('8', '15,9,13,27')
  </code></pre>
  
  <p>Please tell to me equivalent to predefind or userdefined postgresql  function </p>