Notes on Serializability and Locking Schemes -
When multiple Transaction run concurrently, DB consistency can be destroyed, despite the correctness of the each individual Transaction.
To prevent this we use ‘Concurrency-Control Schemes’
The various ‘Concurrency-Control Schemes’ are as:
- Lock-Based Protocols.
- Two-Phase Locking
- Graph-Based Locking (Skip)
- Timestamp-Based Protocol.
- Validation-Based Protocol.
- Multiple Granularity.
- Multiversion Schemes.
Concurrency-Control Schemes - Are used to ensure that the Concurrent Schedules are Serializable.
Serilaizable means - Assuring that a concurrent schedule will ensure consistency or not. i.e Assuring Serilizability.
Serializability can be ensured in two ways-
- Conflict Serializability
- A concurrent schedule is Conflict Serializable if it is conflict equivalent to a Serial Schedule
- View Serializability
- Leave it
Thanks & Regards,
Arun Manglick || Tech Lead