What are the different isolation levels in databases?

What are the different isolation levels in databases?

There are four main isolation levels: Read Uncommitted, Read Committed, Repeatable Read, and Serializable. Each level balances consistency and performance differently.

Can you give me a real-world example of each isolation level?

Sure! For Read Uncommitted, imagine a stock trading app where users can see uncommitted transactions. For Read Committed, think of a banking system where users see only committed transactions. Repeatable Read could be used in an inventory system to prevent stock levels from changing during a transaction. Serializable is often used in financial systems to ensure complete isolation.

What are the trade-offs of using a higher isolation level?

Higher isolation levels provide more consistency but can lead to increased locking and reduced concurrency, which may affect performance.

How do these isolation levels affect performance?

Higher isolation levels can lead to more locks and longer wait times for transactions, which can slow down overall system performance.