Could you explain the meaning of reliability in the context of ACID and why it is important for transactions?

Durability in the context of ACID is a property of a transaction that guarantees that after its successful completion, all data changes are saved and will not be lost even in case of system failures (for example, power outages).

Why is this important:

• Ensures data integrity: after a transaction is committed, the user can be confident that the changes are recorded.
• Prevents data loss in emergency situations.

To implement durability, logging mechanisms (transaction logs) are usually used, which allow restoring the database state after failures.

Example: if you transfer money between accounts, after a successful transaction, the amount is debited from one account and credited to another, and these changes will not disappear even if the server crashes.