OceanBase Database is a distributed relational database. Unlike a centralized database, OceanBase Database is characterized by its distributed capabilities, which contribute to its high scalability and availability.
OceanBase Database adopts the shared-nothing architecture. User data is organized based on log streams and tablets. A tablet stores data and transfers data between servers, and is the smallest unit for data balancing.
In addition, as a distributed database service, OceanBase Database copies the data in the same log stream to multiple OBServer nodes to ensure high availability of data reads and writes. These data copies on different OBServer nodes are called replicas. A log stream group (LS group) is an independent Paxos group that consists of a log stream and its replicas. The Paxos consensus protocol is used to ensure strong consistency among the members. In each LS group, one log stream serves as the leader and the rest as followers. The leader supports strong-consistency reads and writes, and the followers support weak-consistency reads.