What is a race condition in a database transaction, and how does isolation prevent it?
A race condition happens when two transactions read and write overlapping data at the same time, and the final result depends on timing rather than correctness — e.g. two withdrawals both reading the same starting balance before either writes. Isolation levels define how much of that overlap is allowed; higher isolation prevents more race conditions at the cost of more locking or more retries.
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Database Transactions Explained: ACID, Isolation Levels, and Concurrency ControlWhat ACID actually guarantees, and how pessimistic vs optimistic concurrency control decide whether your app locks or retries under load.
Read the full analysisOther questions this article answers
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