C-Store: Concurrency Control and Recovery. Jianlin Feng School of Software SUN YAT-SEN UNIVERSITY Jun. 5, 2009. Concurrency Control vs. Recovery. Concurrency Control Provide correct control of concurrent running of multiple transactions to maximize system throughput .
School of Software
SUN YAT-SEN UNIVERSITY
Jun. 5, 2009
(1) If a transaction T wants to read (respectively, modify) a database object, it first requires a shared (respectively, exclusive) lock on the object.
(2) All locks held by a transaction are released when the transaction is completed.