diff --git a/concepts/analysis_gotchas.md b/concepts/analysis_gotchas.md index 26860b6c..81e09f8e 100644 --- a/concepts/analysis_gotchas.md +++ b/concepts/analysis_gotchas.md @@ -58,6 +58,10 @@ In derived datasets ISO dates are sometimes converted to strings in one of two f Build ids look like dates but aren't. If you take the first eight characters you can use that as a proxy for the day the build was released. +`metadata/Date` is an HTTP Date header in a [RFC 7231](http://tools.ietf.org/html/rfc7231#section-7.1.1.1)-compatible format. + +**Tip:** To parse `metadata/Date` to a usable date in SQL: `DATE_PARSE(SUBSTR(client_submission_date, 1, 25), '%a, %d %b %Y %H:%i:%s')` + ### Delays Telemetry data takes a while to get into our hands. The largest data mule in Telemetry is the main-ping. It is (pending [bug 1336360](https://bugzilla.mozilla.org/show_bug.cgi?id=1336360)) sent at the beginning of a client's _next_ Firefox session. If the user shuts down their Firefox for the weekend, we won't get their Friday data until Monday morning.