title: How to convert a single Oracle datetime into minutes?
body: <p>I wish to convert a single Oracle datetime value to minutes.</p>
  
  <p>As an example, I need to convert the current date/time alone into minutes, i.e.:</p>
  
  <pre><code>select (sysdate)*24*60 from dual
  </code></pre>
  
  <p>but this is giving me an error.</p>
  
  <p>I basically need to perform a check to see that a certain operation cannot be performed until 30 minutes before a particular date/start time, that exists in the database.</p>
  
  <p>So if the Start Time in the DB is: </p>
  
  <p><code>24/04/2014 22:00:00 and the current date/time (SYSDATE) is 24/04/2014 21:29:59</code>,</p>
  
  <p>then operation CANNOT be performed but if the current date/time (SYSDATE) is:</p>
  
  <p><code>24/04/2014 21:30:00</code>, </p>
  
  <p>then operation CAN be performed.</p>