What is ACID?

ACID is a set of properties that guarantee reliable transactions in database management systems:

• Atomicity: the transaction is completed in full or not at all. If something goes wrong, all changes are rolled back.
• Consistency: after the transaction completes, the database remains in a correct state, satisfying all rules and constraints.
• Isolation: concurrent transactions do not affect each other, resulting in outcomes as if they were executed sequentially.
• Durability: once a transaction is committed, the changes are saved and not lost even in case of failures.

These properties ensure data integrity and predictable database behavior when multiple users operate simultaneously.