How does concurrency control work?

Can you explain how concurrency control works in databases?

Sure! Concurrency control is a mechanism that ensures database transactions are executed in a safe manner, preventing conflicts.

What are the different types of concurrency control methods?

There are mainly two types: pessimistic and optimistic concurrency control. Pessimistic locks data to prevent conflicts, while optimistic allows transactions to proceed and checks for conflicts before committing.

How does optimistic concurrency control handle conflicts?

In optimistic concurrency control, transactions proceed without locking resources. Before committing, the system checks if any data has changed. If it has, the transaction is rolled back.

Can you give an example of a situation where concurrency control is necessary?

Certainly! Imagine two users trying to update the same bank account balance simultaneously. Without concurrency control, one update could overwrite the other, leading to incorrect balances.