title: How to add check constraint on time with a timestamp?
body: <p>I need to add a constraint that time entered in a column is only after 8:00 am. I've tried     </p>
  
  <pre><code>alter table toy_store ADD CHECK (store_opening_time &gt; TIMESTAMP '2013-05-05 08:00:00');
  </code></pre>
  
  <p>This only allows entry of timestamp greater than 5th May 8:00 am. I want to write a query that checks if the entry is after 8:00 am notwithstanding the date.</p>