title: Unixtime to Timestamp in sql
body: <p>I want to Convert "632689920000000000"  Unixtime to Timestamp sql.</p>
  
  <p>I already tried </p>
  
  <pre><code>dateadd(s,632689920000000000,'19700101')
  </code></pre>
  
  <p>and </p>
  
  <pre><code>DATEADD(SECOND, 632689920000000000 / 1000, '19691231 20:00')
  </code></pre>
  
  <p>but it returns irrelevent data in each data!!!</p>