Multi-version concurrency control (MVCC) is an implementation of isolation levels based on multiple versions of data. The most frequently used isolation level in SAP HANA is "read committed". This means that every database request sees the committed data of the point in time when the request (not the transaction) started. As a consequence different current and historic versions of the same data may need to be preserved in order to support the points in time when different SQL statements were started.
Multi-version concurrency control (MVCC) is an implementation of isolation levels based on multiple versions of data. The most frequently used isolation level in SAP HANA is "read committed". This means that every database request sees the committed data of the point in time when the request (not the transaction) started. As a consequence different current and historic versions of the same data may need to be preserved in order to support the points in time when different SQL statements were started.