A distributed ACID-compliant database is a type of database system that operates across multiple servers or locations while ensuring properties of ACID: Atomicity, Consistency, Isolation, and Durability. These properties are essential for managing transactions reliably. In a distributed context, the system maintains these properties even when data is spread out over different nodes. This ensures that operations affecting the database behave predictably, even in the face of network failures or node outages.
Atomicity guarantees that all parts of a transaction complete successfully or none at all. For example, if a developer is moving funds from one account to another, the operation should either complete fully or not at all to prevent partial updates, which could lead to inconsistencies. The consistency property ensures that a transaction brings the database from one valid state to another. In a distributed database, if one node updates a value, all nodes must reflect this change promptly to maintain an accurate state across the system. Isolation prevents transactions from interfering with each other, while durability guarantees that once a transaction is committed, it will not be lost, even in the case of a system crash.
Examples of distributed ACID-compliant databases include Google Spanner and CockroachDB. Google Spanner offers global consistency and high availability by employing a unique approach to time synchronization across its distributed nodes. CockroachDB, on the other hand, uses a system of consensus called Raft to ensure that all nodes have the same transactional view of the database, even as it scales horizontally. Choosing a distributed ACID-compliant database can provide developers with the reliability required for critical applications, especially those that need to ensure data integrity across multiple locations.