What is concurrency control in PostgreSQL?

What is concurrency control in PostgreSQL?

Concurrency control in PostgreSQL is a mechanism to manage simultaneous operations without conflicting. It ensures data integrity.

How does PostgreSQL handle transactions in a concurrent environment?

PostgreSQL uses Multi-Version Concurrency Control (MVCC) to handle transactions, allowing multiple transactions to occur simultaneously without locking the database.

What are the different isolation levels available in PostgreSQL?

PostgreSQL supports four isolation levels: Read Uncommitted, Read Committed, Repeatable Read, and Serializable, each providing different guarantees.

Can you explain the difference between Serializable and Repeatable Read?

Serializable isolation prevents phantom reads by ensuring transactions are executed in a way that they appear to be sequential, while Repeatable Read allows for consistent reads within a transaction but can still encounter phantom reads.