title: Equations in ORDER BY statements
body: <p>Say I want to include a  <code>where</code> clause based on two columns, X and Z. I'd then order by <code>(3 * X) + Z DESC</code>.  Is that possible?  I could not find anything about arithmetic in the order by column.   </p>
  
  <p>So the statement would look like:</p>
  
  <pre><code>SELECT * FROM mySweetTable 
  WHERE U LIKE "as%" or V LIKE "as%" 
  ORDER BY (3 * X + Z) DESC
  </code></pre>