Concurrency control is an essential aspect of database systems that deals with multiple concurrent transactions. PostgreSQL employs various techniques to ensure concurrent access to the database while maintaining data consistency using atomicity and isolation of ACID (stands for Atomicity, Consistency, Isolation and Durability – https://en.wikipedia.org/wiki/ACID) properties.
Concurrency Techniques
Broadly there are three concurrency techniques available for any database management system, pessimistic, optimistic, and multi-valued concurrency control (MVCC). In this section, I will introduce the techniques.
Pessimistic Locking
This concurrency control technique is used in database systems to handle concurrent access to shared data. It takes a cautious approach by assuming