title: Concat multiple rows with a delimiter in Hive
body: <p>I need to concat string values row wise with '~' as delimiter.
  I have the following data:</p>
  
  <p><a href="https://i.stack.imgur.com/Ozk6u.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Ozk6u.png" alt="enter image description here"></a></p>
  
  <p>I need to concat 'Comment' column for each 'id' in the ascending order of 'row_id' with '~' as delimiter.</p>
  
  <p>Expected output is as below:</p>
  
  <p><a href="https://i.stack.imgur.com/F01qZ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/F01qZ.png" alt="enter image description here"></a></p>
  
  <p><code>GROUP_CONCAT</code> is not an option since its not recognized in my Hive version.
  I can use <code>collect_set</code> or <code>collect_list</code>, but I won't be able to insert delimiter in between. </p>
  
  <p>Is there any workaround?</p>