Lock-Based Concurrency Control and Two-Phase Locking
A concurrency-control protocol decides, operation by operation, whether a transaction may proceed, must wait, or must abort, so that every schedule it lets through is serializable.
Database Management Systems · topic
Concurrency control and recovery
Shared and exclusive locks and their compatibility, basic, strict, rigorous and conservative two-phase locking, deadlock handling with wait-die and wound-wait, timestamp ordering and the Thomas write rule, and a short note on log-based recovery with undo and redo.
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Timestamp-Based Concurrency Control
Locking discovers a serialization order at run time, through the order of lock points. Timestamp ordering fixes the order in advance: every transaction gets a unique timestamp when it starts, and the system allows a conflicting operation only if it respects timestamp order.
Concurrency control and recovery cheat sheets
One-page visual sheets for this topic, in the sheet library on the store. Previews are free; the full sheets come with the subject pack.