ACID properties ensure database reliability:
- Atomicity: Transactions are all-or-nothing. If any part fails, the entire transaction rolls back
- Consistency: Database remains in a valid state before and after transactions
- Isolation: Concurrent transactions don't interfere with each other
- Durability: Committed changes persist even after system failures
Example:
BEGIN;
UPDATE accounts SET balance = balance - 100 WHERE id = 1;
UPDATE accounts SET balance = balance + 100 WHERE id = 2;
COMMIT; -- Both operations succeed or both fail