FACILITATING DATA MIGRATION BETWEEN DATABASE CLUSTERS WHILE THE DATABASE CONTINUES OPERATING

摘要

A system for migrating data items from a source cluster to a destination cluster in a database system. During operation, while the database continues to process live database traffic, the system records a current position in an operation log for the database, wherein the operation log comprises a sequential record of operations applied to the database. Next, the system retrieves data items from the source cluster, and inserts the copies of the retrieved data items into the destination cluster. The system also applies a sequence of updates, starting from the recorded position in the operation log, to the copies of the data items in the destination cluster. Finally, after the sequence of updates is applied, the system performs a cut-over operation that diverts the live database traffic from the data items on the source cluster to the copies of the data items on the destination cluster.