title: How to mask a mobile phone number portion with 'X'
body: <p>Using Oracle SQL, how can I replace certain numbers with an 'X'.</p>
  
  <p>For example, if I have a random mobile number: </p>
  
  <p><code>0400 100 200 or 0400100200</code> </p>
  
  <p>I would like to mask out the number to: </p>
  
  <pre><code>0400 XXX XXX and 0400XXXXXX
  </code></pre>
  
  <p>I have tried using TRANSLATE but unsure if this is the best approach.</p>