title: Get a timestamp from concatenating day and time columns
body: <p>I am having day and time fields in database. I want to get the time-stamp by concatenating the day and time. How to do this in PostgreSQL?</p>
  
  <p>I have done this:</p>
  
  <pre><code>SELECT EXTRACT(EPOCH FROM TIMESTAMP '2011-05-17 10:40:28');
  </code></pre>
  
  <p>And it is working fine.</p>
  
  <p>But when I tried replacing day and time fields I am getting the following error:</p>
  
  <pre><code>SELECT EXTRACT(EPOCH FROM TIMESTAMP Day || ' ' || Time);
  </code></pre>
  
  <blockquote>
  <pre><code>ERROR:  syntax error at or near "Day"
  LINE 1: ...quest_count &gt; 0 AND (EXTRACT(EPOCH FROM TIMESTAMP Day || ' ' || Time)) &gt; (e...
  </code></pre>
  </blockquote>