title: MySQL can I use regex to denote the type of a row?
body: <p>I have a 'User' table with a column:</p>
  
  <pre><code>USERNAME varchar(40)
  </code></pre>
  
  <p>A 'User' can either be a management user, or a standard user.  Management users always contain purely numeric usernames.</p>
  
  <p>I can then use regex to pull out all the users with numeric names to get the management users, and vice versa to get the non management.  </p>
  
  <p>Is it okay practice to therefore use regex in my select queries to get this information, or should I instead add an additional column:</p>
  
  <pre><code>MANAGEMENT TINYINT(1)
  </code></pre>
  
  <p>Which stores whether a user is a management user or not.</p>
  
  <p>What is best practice and why?</p>