title: Why is SUBSTRING(DateUpdated,0,11) different than the first 11 characters of DateUpdated?
body: <p>I'm assuming this is some sort of timezone offset issue, but can anyone explain exactly what is happening here?  Note that this is <a href="/questions/tagged/intersystems-cache" class="post-tag" title="show questions tagged &#39;intersystems-cache&#39;" rel="tag">intersystems-cache</a>.</p>
  
  <pre><code>SELECT 
      DateUpdated,
      TimeUpdated, 
      SUBSTRING(dateUpdated,0,11) as DU, 
      SUBSTRING(timeUpdated,0,11) as TU
  FROM Schema.Table
  </code></pre>
  
  <p><img src="https://imgur.com/r773MVx.png"></p>
  
  <p>Why is <code>SUBSTRING(DateUpdated,0,11)</code> different than the first 11 characters of <code>DateUpdated</code>?</p>