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relational database

ACID Properties

ACID stands for Atomicity, Consistency, Isolation, and Durability — four guarantees that ensure reliable database transactions. Atomicity means all-or-nothing execution. Consistency ensures only valid data is written. Isolation prevents concurrent transactions from interfering. Durability guarantees committed data survives crashes.

Use Cases

  • •Bank transfers where money must leave one account and arrive in another atomically
  • •Enforcing business rules like 'account balance cannot go negative' via consistency checks
  • •Handling concurrent purchases of limited inventory without overselling
  • •Ensuring completed orders are never lost even if the server crashes immediately after

Visualization

BEFOREaccountsidnamebalance1Alice10002Bob500
Speed:1x
Transfer $200 from Alice to Bob — must be atomicStep 1 / 7

Implementation

Output

Click "Run Code" to see output...