title: Azure data factory - mapping data flows regex implementation to format a number
body: <p>I am creating a mapping data flow where I have a phone number column which can contain values like
  (555) 555-1234 or
  (555)555-1234 or
  555555-1234</p>
  <p>I want to extract numbers from this value. How can that be done. I have tried the below function with different variations but nothing is working.</p>
  <p>regexExtract(&quot;(555) 555-1234&quot;,'\d+)')</p>
  <p>regexExtract(&quot;(555) 555-1234&quot;,'(\d\d\d\d\d\d\d\d\d\d)')</p>