What are the main functions and the purpose of ACID principles in transaction management?

The ACID principles ensure reliability and correctness of transactions in databases:

• Atomicity — a transaction is completed in its entirety or not at all. If one part of the operation fails, all changes are rolled back.
• Consistency — a transaction transforms the database from one valid state to another, adhering to all rules and constraints.
• Isolation — concurrent transactions do not affect each other as if they were executed sequentially.
• Durability — after a transaction is committed, its changes are permanent even in the event of system failures.

These properties guarantee that data in the database remains consistent and reliable when multiple operations are performed simultaneously.