title: How to add string to MYSQL database, and deleting last character of string in it using php?
body: <p>I want to <em>add</em> the string <code>,'2')</code> to a row in my database. The current string in the database looks like this: <code>('1','42','2122','3')</code>
  If I was to add it normally, this would be the result: <code>('1','42','2122','3'),'2')</code>. 
  How can I delete the last character of the string, that is already in the database, so it will end up like this: <code>('1','42','2122','3','2')</code>
  I tried using <code>concat</code> and (sub)<code>str_replace</code>, but that did not give me the desired result. </p>
  
  <p>Is this possible using SQL only, without first fetching the record and updating it?</p>