beginnerLocking — Optimistic vs Pessimistic

What is the difference between optimistic and pessimistic locking?

Pessimistic locking: assumes conflicts are frequent. Locks the resource before accessing it. SQL: SELECT ... FOR UPDATE. Other transactions are BLOCKED until the lock is released. Guarantees exclusive access during the transaction. Good for: high-conflict scenarios, financial transactions where conflicts are expected. Optimistic locking: assumes conflicts are rare. No locks taken. On write: verifi

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