The acronym ACID stands for Atomicity, Consistency, Isolation and Durability.
These are group of properties that every DBMS must satisfy. Any database is said to be reliable, if it meets all these properties. Otherwise, we consider that DBMS as not reliable.
Let’s drown deep in ACID
This is called all or nothing rule. i.e., All the operations in a transaction will be completed or will not be executed at all. If one of the operation fails in a transaction, then entire transaction will be failed.
It ensures that by the end of a transaction, the system will be in a valid state. That means only valid data will be committed. If the transaction is completed successfully, then the system will be in valid state. Otherwise, changes will be rolled back to make the system valid.
It ensures that, transactions are processed without interference. That means, one transaction cannot read the data from another transaction until it executes completely. If two people are invited to attend an interview at the same time, then second person can’t enter into the interview room until the first person completes.
It ensures that a transaction which was committed to the database will be permanent.