Troubleshoot missing events in the Unified model

This article describes the most common reasons that events might be missing from the Unified model derived tables.

Events are dropped to the quarantined_sessions table

A session is quarantined if it's total duration exceeds the maximum specified in the snowplow__max_session_days variable which has a default value of 3. Those sessions are moved to the snowplow_base_quarantined_sessions table. Usually, those sessions are produced by bot activity (e.g. user producing an unusual number of page_view events).