title: How to truncate timestamp to minutes?
body: <p>I have to subtract 5 minutes from current timestamp and floor(truncate) it to nearest minute. Like '2016-02-23 06:10:39.0' should be '2016-02-23 06:05:00.0'.
  I have found way to subtract 5 minutes as </p>
  
  <pre><code> systimestamp - interval '5' minute
  </code></pre>
  
  <p>EDIT 1:
  I need timestamp in particular format,</p>
  
  <pre><code> TO_TIMESTAMP((systimestamp - interval '15' minute),'YYYY-MM-DD HH24:MI:SS.ff')
  </code></pre>
  
  <p>But this is giving </p>
  
  <pre><code>ORA-01830: date format picture ends before converting entire input string
  </code></pre>
  
  <p>But I am not able to floor it to nearest minute. 
  Please help. Thanks</p>