title: difference between UNHEX and X (MySQL)
body: <p>What really is the difference between MySQL UNHEX and X when dealing with hexadecimal values in a database?</p>
  
  <p>Eg. </p>
  
  <pre><code>SELECT * FROM test WHERE guidCol IN (UNHEX('hexadecimalstring'));
  
  SELECT * FROM test WHERE guidCol IN (X'hexadecimalstring');
  </code></pre>
  
  <p>Both gives me exact result set. So is there any difference? Performance implications?</p>
  
  <p><strong>Edit:</strong> the underlying type of guidCol is binary of course</p>