Database Management Systems · Transactions and concurrency

Isolation levels

How much of those concurrency anomalies a database is willing to allow, chosen as a tradeoff against speed.

Also known as: READ COMMITTED, SERIALIZABLE, isolation guarantees.

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• Concurrency anomalies: The specific bad things that can happen when two transactions run at the same time: dirty, non-repeatable, and phantom reads.

Related topics

• Lock-based concurrency control: Transactions acquiring then releasing locks on data, in two strict phases, to enforce serializability in practice.