title: Manipulating dates in the datastore
body: <p>I've recently been playing around with Google's AppEngine and I seem to have gotten stuck. I'm trying to create a query that selects posts that are before a certain date (in this case, the date is now - 1 day). I've tried a few different methods in order to accomplish this, but none have worked. One of which involved converting all the dates to UNIX time and running a query like this:</p>
  
  <pre><code>db.GqlQuery("SELECT __key__ FROM Post WHERE date-84600 &lt; %s LIMIT 10, ORDER BY date DESC" % time.time())
  </code></pre>
  
  <p>But after trying that, I got a syntax error which told me GQL didn't have support for operations such as subtracting in the queries.</p>
  
  <p>Does anyone have any idea as to how I could accomplish this?</p>
  
  <p>Thanks in advance</p>