title: Oracle: Replacing non-numeric chars in a string
body: <p>I have a field in my database where users have saved free-form telephone numbers. As a result, the data has all sorts of different formatting:</p>
  
  <ul>
  <li>(area) nnn-nnnn</li>
  <li>area-nnn-nnnn</li>
  <li>area.nnn.nnnn</li>
  <li>etc</li>
  </ul>
  
  <p>I would like to strip out all the non-numeric characters and just store the digits, but I can't find a simple way to do this. Is it possible without using one REPLACE for each char?</p>