What are the differences between locking and timestamp ordering in databases?

What are the differences between locking and timestamp ordering in databases?

Locking and timestamp ordering are two concurrency control mechanisms in databases. Locking prevents multiple transactions from accessing the same data simultaneously, while timestamp ordering ensures that transactions are executed in the order of their timestamps.

Can you explain how locking works in more detail?

Sure! Locking involves placing a lock on a data item when a transaction wants to read or write it. There are different types of locks, such as shared locks for reading and exclusive locks for writing. This prevents other transactions from accessing the locked data until the lock is released.

What are the advantages of using timestamp ordering?

Timestamp ordering allows for greater concurrency since transactions can proceed without waiting for locks. It also helps in maintaining a consistent view of the database by ensuring that transactions are executed in the order they were initiated.

Are there any drawbacks to using either method?

Yes, locking can lead to deadlocks if two transactions wait on each other to release locks. Timestamp ordering can suffer from starvation, where some transactions may never get executed if they keep getting delayed by newer transactions.