What Is MVCC?

Answer: MVCC refers to Multi-Version Concurrency Control. MVCC is a database concurrency control protocol. A write transaction does not modify the tuple content immediately. Each operation creates a target version based on the source version and retains the source version. When a transaction needs to read data, the database system selects a version that meets the transaction isolation level requirement from all versions.

A main advantage of the MVCC is that MVCC does not cause conflicts between lock requests for data reading and writing and keep them unaffected by each other.