title: Hive and regular expression
body: <p>I am trying to filter all the ip adresses in a username. But this doesnt really work properly in my query:</p>
  
  <pre><code>select distinct regexp_extract(username, '^([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})$', 0) from ips. 
  </code></pre>
  
  <p>The problem is that he even recognizes numbers as 1000000 as ip adress.
  Any idea how to fix it?</p>