ACID Vs BASE - A definition
ACID is a characteristic of RDBMS databases
Atomic: Each task in a transaction succeeds or the entire transaction is rolled back.
Consistent: A transaction maintains a valid state for the database before and after its completion and cannot leave the database in an inconsistent state.
Isolated: A transaction not yet committed must not interfere with another transaction and must remain isolated.
Durable: Committed transactions persist in the database and can be recovered in case of database failure.
BASE is a characteristic of NoSQL databases
Basically Available: The system is guaranteed to be available in event of failure.
Soft State: The state of the data could change without application interactions due to eventual consistency.
Eventual Consistency: The system will be eventually consistent after the application input. The data will be replicated to different nodes and will eventually reach a consistent state. But the consistency is not guaranteed at a transaction level.
The BASE systems allow horizontal scaling, fault tolerance, and high availability at the cost of consistency.