title: MySQL IFNULL question
body: <p>I have a query which contains a subquery which is something like this</p>
  
  <pre><code>IFNULL((SELECT id FROM mytable WHERE id = 1), 'No')
  </code></pre>
  
  <p>It works OK, but I would like to return the string 'Yes' on success rather than the actual id of the row.</p>
  
  <p>Is there any way to override the value it returns?</p>
  
  <p>Thanks.</p>