MVCC
MVCC (Multi-Version Concurrency Control) is a database concurrency control method that allows multiple transactions to access the same data simultaneously without blocking each other, by maintaining multiple versions of data items. It enables high concurrency and isolation levels like snapshot isolation, commonly used in relational and NoSQL databases to improve performance and avoid locks. Each transaction sees a consistent snapshot of the database as of its start time, with changes visible only after commit.
Developers should learn MVCC when working with databases that require high concurrency and scalability, such as in web applications or distributed systems, to prevent read-write conflicts and deadlocks. It is essential for implementing ACID-compliant transactions in systems like PostgreSQL, Oracle, and MySQL (with InnoDB), and for understanding how databases handle isolation in multi-user environments. Use cases include financial systems, e-commerce platforms, and any application with frequent concurrent reads and writes.