What is optimistic control in database systems?

What is optimistic control in database systems?

Optimistic control is a concurrency control method that assumes transactions will not conflict. It allows transactions to execute without locking resources, validating them before committing.

How does it differ from pessimistic control?

Unlike pessimistic control, which locks resources to prevent conflicts, optimistic control allows transactions to proceed without locks, checking for conflicts only at commit time.

What are the advantages of using optimistic control?

The main advantages include increased throughput, reduced waiting time for transactions, and better performance in environments with low contention.

Are there any drawbacks to optimistic control?

Yes, if conflicts are frequent, it can lead to increased rollbacks and wasted resources, making it less efficient in high-contention scenarios.

Can you give an example of where optimistic control is used?

It's commonly used in applications like online transaction processing systems where the likelihood of transaction conflicts is low.