Multiversion Concurrency Control

In computer science, in the field of databases, multiversion concurrency control (abbreviated MCC or MVCC) is a concurrency control method commonly used by database management systems to provide concurrent access to the database.From the perspective of the client, MVCC provides each user connected to the database with a "snapshot" of the database for that person to work with. Any changes made will not be seen by other users of the database until the transaction has been committed.
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