What is Atomicity?

Atomicity refers to the concept of atomic operations or transactions in computer science and database systems. An atomic operation is an indivisible and irreducible unit of work. It means that either the entire operation is performed, or none of it is.

In the context of databases, atomicity ensures that a transaction is treated as a single, all-or-nothing unit of work. A transaction typically consists of multiple database operations, such as reading or updating data. Atomicity guarantees that if any part of the transaction fails, the entire transaction is rolled back, and the database returns to its original state before the transaction began.

For example, suppose you are transferring money from one bank account to another. The transaction involves subtracting the amount from the sender’s account and adding it to the receiver’s account. If the withdrawal operation succeeds but the deposit operation fails due to a network issue or any other reason, atomicity ensures that the withdrawal operation is rolled back, and the sender’s account is not debited. This prevents inconsistent or partial updates to the database.

Atomicity is one of the ACID properties in database systems. ACID stands for Atomicity, Consistency, Isolation, and Durability. These properties ensure reliable and consistent database transactions, even in the presence of failures or concurrent access.