Source/medium for direct hits in session streaming

In hit streaming tables, the traffic.source and traffic.medium fields contain values taken directly from the UTM tags in the pagePath (&dr and &dl parameters) for a given hit.

In the session streaming tables, the data in the trafficSource.source and trafficSource.medium fields is based on the session data in Google Analytics.

Since the Last Non-Direct Click attribution model is applied by default in Google Analytics reports, direct traffic is ignored, and 100% of the conversion value is attributed to the last non-direct channel that a customer clicked through from before buying or converting. All Direct visits are ignored within 6 months after the non-direct visit.

Thus, it would be incorrect to compare referral data in the session streaming to the data in the hit streaming.