Dealing With Contention hard
Most modern databases resolve deadlocks automatically by:
- A Detecting the cycle and selecting a 'Victim' transaction (e.g., the one with the least work done) to Rollback/Kill.
- B Stopping the server.
- C Sending an email to the admin.
- D Unlocking both rows.
Answer: A. Detecting the cycle and selecting a 'Victim' transaction (e.g., the one with the least work done) to Rollback/Kill.
Apps must handle this `DeadlockVictimException` by retrying. It is routine behavior, not an error.
One system design question a day, with spaced repetition so the ones you miss come back.
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