What is lock granularity in database systems?

What is lock granularity in database systems?

Lock granularity refers to the size of the data item that a lock protects, such as a row, page, or table.

Why is lock granularity important?

It's important because it affects concurrency and performance; finer granularity allows more concurrent access but can increase overhead.

Can you give an example of different lock granularities?

Sure! For instance, row-level locks allow multiple transactions to access different rows in a table simultaneously, while table-level locks prevent any other transaction from accessing the entire table.

What are the trade-offs between fine and coarse lock granularity?

Fine granularity improves concurrency but increases overhead, while coarse granularity reduces overhead but can lead to contention and reduced performance.