Data Fundamentals - datageekshub.com

Atomicity	Consistency	Isolation	Durability
Means All or nothing rule / Atomic / Single Unit	Means consistent / value should always be preserved	Means Separation	Means permanency of something
The entire transaction takes place or doesn’t happen at all	The Database must be consistent before and after the transaction	Multiple transactions should occur independently without interference	The changes of a successful transactions should appear even after system failure
Atomicity is also known as the ‘All or nothing rule’.	It refers to the correctness of a database.	Transactions occur independently without interference.	This property ensures that once the transaction has completed execution, the updates and modifications to the database are stored in and written to disk and they persist even if a system failure occurs.
Atomicity ensures that a transaction is treated as a single, indivisible unit of work	Consistency ensures that a transaction takes the database from one consistent state to another consistent state.	Isolation ensures that multiple transactions can execute concurrently without interfering with each other. Each transaction must be isolated from other transactions until it is completed.	Durability ensures that once a transaction is committed, its changes are permanent and will survive any subsequent system failures.
There is no midway i.e. transactions do not occur partially.	This means that integrity constraints must be maintained so that the database is consistent before and after the transaction.	Changes occurring in a particular transaction will not be visible to any other transaction until that particular change in that transaction is written to memory or has been committed.	These updates now become permanent and are stored in non-volatile memory.
It involves the following two operations. — Abort: If a transaction aborts, changes made to the database are not visible. — Commit: If a transaction commits, changes made are visible.