title: MySQL datetime where clause query help
body: <p>What I have is a query that updates a column called "active".  Right now my query is:</p>
  
  <pre><code>UPDATE MainTable
     SET active = b'0'
   WHERE lastprocessdate &lt; '5/21/2011'
  </code></pre>
  
  <p>Unfortunately, this updates everything -- which is impossible because everything has today's date on it.  <code>lastprocessdate</code> is a <code>datetime</code> column, that originally is processed using <code>NOW()</code>.</p>