Is it possible to ensure ACID in Redis?

Redis is not originally a fully ACID-compliant system, as it is focused on high performance and scalability.

• Atomicity: Redis supports atomicity of individual commands and transactions with MULTI/EXEC — all commands within a transaction are executed sequentially without interruption.

• Consistency: Redis ensures data consistency within a single node.

• Isolation: Redis transactions do not support lock-level isolation; commands within MULTI/EXEC are executed sequentially, but there is no rollback on errors.

• Durability: By default, Redis stores data in memory and periodically writes to disk (RDB snapshot) or logs commands (AOF). This provides some resilience, but data can be lost in case of failures.

Thus, Redis can be considered partially ACID:

• Commands and transactions are atomic.
• Full isolation and guaranteed durability are not provided.

To ensure strict ACID properties, additional mechanisms or external systems should be used, or Redis should be considered as a cache or fast storage with reliability trade-offs.