Answer
A transaction isolation level controls which effects of concurrent transactions may be observed. • Stronger isolation prevents more anomalies but can require retries or more coordination. • SQL defines named levels, while exact implementation behavior varies by database. • Applications must choose a level that protects their business rules.
💡 SQL Example
SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
Result
SET
⚡ Quick Revision
Isolation levels control visibility and anomalies between concurrent transactions.