title: Duplicate Column Values MySQL
body: <p>Is there a way I can duplicate a column's values into another column?</p>
  
  <p>IE:</p>
  
  <pre><code>s_id  img_id
  1     -
  2     -
  3     -
  4     -
  </code></pre>
  
  <p>to </p>
  
  <pre><code>s_id  img_id
  1     1
  2     2
  3     3
  4     4
  </code></pre>