Answer
Database locking coordinates concurrent access to database objects or rows. • Locks can protect data while a statement or transaction operates. • Conflicting locks can make another transaction wait. • Lock mode, duration, and granularity depend on the operation and database.
💡 SQL Example
SELECT * FROM accounts WHERE account_id = 1 FOR UPDATE;
Result
The selected row is locked for update
⚡ Quick Revision
Locks coordinate concurrent operations on shared data.