What is the difference between transaction isolation and locking?

What is the difference between transaction isolation and locking?

Transaction isolation refers to the level of visibility that one transaction has to the changes made by other concurrent transactions. Locking, on the other hand, is a mechanism used to control access to data to prevent conflicts between transactions.

Can you explain the different levels of transaction isolation?

Sure! The main levels of transaction isolation are Read Uncommitted, Read Committed, Repeatable Read, and Serializable. Each level provides a different balance between consistency and performance.

How do locks affect performance in a database?

Locks can significantly affect performance by causing contention among transactions. If many transactions are waiting for locks, it can lead to delays and reduced throughput.

What are some common locking mechanisms used in databases?

Common locking mechanisms include row-level locks, table-level locks, and optimistic locking. Each has its own use cases and trade-offs.