title: Trim commas with MySQL?
body: <p>I have a list of keywords like below and some keyword lists in the database have a leading or trailing <code>,</code></p>
  
  <pre><code>keyword,keyword,keyword,keyword,
  </code></pre>
  
  <p>How do I trim the leading and/or trailing <code>,</code> using mysql?</p>
  
  <p>I have tried using <code>trim</code> but can't seem to get it to work on an <code>UPDATE</code>, which is what I'm trying to achieve.</p>