title: Inspect `mysqli::errno` after UPDATE query to decide if trigger FATAL error or WARNING
body: <p>After an UPDATE query with <code>mysql::query()</code> I can check the <code>mysqli::error</code> or <code>mysqli::errno</code>to get the error message or number.</p>
  
  <p>This is useful to log the error, but I should decide based on the severity of the error what to do.</p>
  
  <ul>
  <li>If it is a logic error (row does not exist, values are not valid) I should abort execution.</li>
  <li><p>If the data base was not reachable, or something similar I should just log the error but not halt the program execution.</p>
  
  <ol>
  <li>I can inspect the error number, for example error 1054 is returned when a column is unknown. The problem is mysql manual lists near 1000 errors, so check which ones are relevant seems no the way to go and can be very risky if I miss just one error condition relevant to the problem.</li>
  <li>Other problem is when the row is not in the table since no error is returned.</li>
  </ol></li>
  </ul>
  
  <p>What is the common approach to check this condition?</p>