Lost Update
Lost Update is a database concurrency anomaly in which two concurrent transactions read the same data and update it based on that read, and the later-committing transaction overwrites the modification of the earlier-committing one, so the earlier update is lost. In financial systems it can cause loss of funds and reconciliation failures.
Timeline (last 90 days)
Under a relaxed isolation level, if there is no explicit concurrency control, two concurrent transactions issuing non-atomic updates based on the same read will cause a lost update anomaly, resulting in lost funds and end-of-day reconciliation failures.
The race condition example in which two concurrent withdrawal requests each for 60.00 successfully withdraw 120.00 from an account with a balance of 100.00 illustrates the flaws of mutable state.
All Facts (2)
Under a relaxed isolation level, if there is no explicit concurrency control, two concurrent transactions issuing non-atomic updates based on the same read will cause a lost update anomaly, resulting in lost funds and end-of-day reconciliation failures.
50%UnverifiedThe race condition example in which two concurrent withdrawal requests each for 60.00 successfully withdraw 120.00 from an account with a balance of 100.00 illustrates the flaws of mutable state.
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