title: regexp extract in google data studio
body: <p>I want to create a calculated field in google data studio which only returns the numbers at the beginning of a string which could look like this:</p>
  <pre><code>123-something-something1
  or
  32-something-something2
  or
  1234-somthing-something3
  </code></pre>
  <p>I thought that I had the right regex but it's only returning null which means the regex is wrong.</p>
  <p>The regex's i've tried:</p>
  <pre><code>REGEXP_EXTRACT(Campagne, '.*')
  REGEXP_EXTRACT(Campagne, '^[0-9].[0-9]*')
  REGEXP_EXTRACT(Campagne, '[0-9].[0-9]*')
  REGEXP_EXTRACT(Campagne, '^[0-9]*')
  REGEXP_EXTRACT(Campagne, '[0-9]*')
  REGEXP_EXTRACT(Campagne, '^[0-9].[0-9]*')
  REGEXP_EXTRACT(Campagne, '[0-9].[0-9]*')
  </code></pre>
  <ul>
  <li><code>^</code> this should stand for the beginning of the value</li>
  <li><code>[0-9]</code> should count any number</li>
  <li><code>.</code> should match any character</li>
  <li><code>*</code> counts as an multiplier for the previous character</li>
  </ul>
  <p>Really hope someone can help me out since I can't get it to work</p>