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.
All the operations in a transaction will be completed or will not be executed at all.
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.
It ensures that, transactions are processed without interference. That means, one transaction cannot read the data from another transaction until it executes completely.
It ensures that a transaction which was committed to the database will be permanent.
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