title: mysql update multiple columns with same now()
body: <p>I need to update 2 datetime columns, and I need them to be exactly the same, using mysql version 4.1.20. I'm using this query:</p>
  
  <pre><code>mysql&gt; update table set last_update=now(), last_monitor=now() where id=1;
  </code></pre>
  
  <p>It is safe or there is a chance that the columns are update with different time, because of the 2 visible calls to <code>now()</code>?<br>
  I don't think that it can be update with different values (I think internally mysql calls <code>now()</code> just once per row or something similar), but I'm not an expert, what do you think?</p>
  
  <p><strong>Update:</strong>
  Second question was extracted <a href="https://stackoverflow.com/questions/56269245/update-multiple-columns-with-same-value-short-syntax">here</a>.</p>