title: query metrics on tag value with regex in datadog
body: <p>I want to filter metrics on tag value with a regex. I can do it in Prometheus but I could not find an equivalent way in Datadog. </p>
  
  <p>For example, to select the following metric whose <code>status</code> tag value starts with <code>2</code>, I can use the query <code>http.server.requests.count{status=~"^2..$"}</code></p>
  
  <p>I have the same metric with the same tags in Datadog too, but couldn't find a way to have the same query.</p>