Serializability
Serializability is the highest isolation level: concurrent transaction results are equivalent to some serial execution order, completely eliminating concurrency anomalies.
Purpose
To provide the strongest concurrency correctness guarantee, for scenarios with strict correctness requirements.
Mechanism
Implemented via two-phase locking (2PL), serializable snapshot isolation (SSI), or OCC. The cost is reduced concurrency and deadlock risk. PostgreSQL SSI rolls back on detecting write-skew anomalies.
Use cases
- Transaction isolation design
- Concurrency correctness
- Database isolation levels