What did you know and when did you know it? The MarkLogic® Bitemporal feature answers this critical question by tracking when events occurred (valid time) in combination with when they were recorded (system time). More powerful than a traditional unitemporal database, a bitemporal database allows you to query across valid and system time axes. You can go back in time and explore data, manage historical data across systems, ensure data integrity, and do complex bitemporal analysis with ease.