ScyllaDB in Action Book Excerpt: ScyllaDB, a Distributed Database

ScyllaDB is a distributed database system that achieves scalability and fault tolerance by dispersing and replicating data across multiple nodes without following a leader-follower topology, allowing any node to serve as a coordinator for data requests. It employs a hash ring system to map data to nodes, supporting tunable consistency levels to balance between availability and consistency, thus classifying it as an AP system according to the CAP theorem. With options like quorum-based consistency, ScyllaDB can maintain availability even during network partitions, although this may lead to eventual consistency where data converges over time. By prioritizing availability, ScyllaDB differentiates itself from traditional relational databases and aligns with the PACELC theorem's notion of trading off consistency for latency in specific scenarios.