title: Subtracting a week from UNIX_TIMESTAMP
body: <p>I have a query:</p>
  
  <pre><code>SELECT * FROM msc_calendar WHERE calendar_userId = 1 AND end &lt; UNIX_TIMESTAMP() 
  </code></pre>
  
  <p>Is there a way to subtract a week from the timestamp, i.e. to see if <code>end</code> was more than a week ago?</p>