Answer
The standard isolation level names are Read Uncommitted, Read Committed, Repeatable Read, and Serializable. • Read Committed allows each statement to see a fresh committed snapshot in PostgreSQL. • Repeatable Read keeps a stable transaction snapshot in PostgreSQL. • Serializable provides the strongest guarantee but transactions may need retrying.
💡 SQL Example
BEGIN TRANSACTION ISOLATION LEVEL REPEATABLE READ;
Result
BEGIN
⚡ Quick Revision
Isolation levels trade concurrency behavior against protection from anomalies.