Belief time; Extrinsic time; Physical time; Registration time; System time; Transaction commit time
A database fact is stored in a database at some point in time, and after it is stored, it remains current, or part of the current database state, until it is logically deleted. The transaction time of a database fact is the time when the fact is current in the database. As a consequence, the transaction time of a fact is generally not a time instant but rather has duration.
The transaction time of a current fact extends from some time in the past until the (growing) current time. A current fact can be deleted by replacing its growing end time with the fixed time when the deletion occurs.
In the context of a database management system that supports user transactions, the transaction times of facts are consistent with the serialization order of the transactions that inserted or logically deleted them. Transaction times may be implemented using transaction commit times...
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