Terminologies used in Oracle NoSQL Database

Some of the terminologies used in Oracle NoSQL Database

Release: Oracle NoSQL Database is released three times in a year. The release number of the Oracle NoSQL database follows this pattern release.major.minor where release is the last 2 characters of the year(For example: 23), major release number denotes the quarter which is 1,2, or 3 and minor release number is the final patch number of the release. For example : 23.1.16.

Data Store: Oracle NoSQL Database applications read and write data by performing network requests against an Oracle NoSQL Database data store. The data store is a collection of Storage Nodes, each of which hosts one or more replication nodes.

host: The hostname associated with the Storage Node on which the data store is installed. A hostname is a unique term assigned to a Storage Node on a network. It distinguishes one Storage Node from another on a specific network.

port: The TCP/IP port through which the Storage Node connects to the Oracle NoSQL Database. This port must be free on the Storage Node. The default port used is 5000. This port is referred to as the registry port.

KVROOT: A directory that stores the data of your data store and security related information. There should be enough disk space on each Storage Node to hold the data of your data store. It is recommended that you use the same directory path for $KVROOT on each of the Storage Nodes in the installation.

Storage Node: A Storage Node is a physical (or virtual) machine with its own local storage, which houses the Replication Node.

Replication Node: Every Storage Node hosts one or more replication nodes(RN) as determined by its capacity. A Storage Node's capacity serves as a rough measure of the hardware resources associated with it (memory, CPUs, and disks). , each of which hosts one or more replication node.

Admin service: An administrative process that runs on a Storage Node and runs various Admin CLI commands.

Managed service: The replication node process that run on a Storage Node.

Storage Node Agent: . The Storage Node Agent manages all the Replication Nodes running on the Storage Node (host)

Shard: A shard is a horizontal partition of data in a database. Your data store's replication nodes are organized into shards. A single shard contains multiple replication nodes.

Majority in a Shard: The number of replication nodes which are available and online in a shard. This will help in ensuring read and write availability in the shard and to elect master when one of the nodes fail.

Master Node and Replica Nodes: There are two types of Replication Nodes, namely, master and replica. Each shard must contain one master node. The master node performs all database write activities. Each shard can also contain one or more read-only replicas. The master node copies all new write activity data to the replicas. The replicas are then used to service read-only operations.

Quorum: Quorum is the minimum number of primary nodes required in a shard, or in the set of admin nodes, to permit electing a master to support write operations.

Zone: A zone is a physical location that supports high-capacity network connectivity between the Storage Nodes deployed within it.

Master Affinity Zones: Master Affinity is a way for you to indicate which primary zones can host master replication nodes. Master Affinity zones service high demand "write" requests across shards.

Replication factor: The total number of masters and replicas in a shard are equal to the replication factor (RF). You can also think of Replication Factor as the number of copies of your data.

Zone Replication factor: The number of copies, or replicas, maintained in a zone.

Primary Replication factor: The total number of replicas in all primary zones.

Secondary Replication factor: The total number of replicas in all secondary zones.

Store Replication factor:The total number of replicas in all zones across the entire store.

Arbiter Node: An Arbiter Node is a lightweight process that is capable of supporting write availability when the primary replication factor is two and a single replication node becomes unavailable or when two replication nodes are unable to communicate to determine which one of them is the master.

Multi-Region data store: Oracle NoSQL Database supports creating tables in multiple data stores, and still maintain consistent data across these clusters. If you have replicated data across data stores, it is called a multi-region data store.

Xregion Service Agent: In a Multi-Region data store, a Cross-Region Service or XRegion Service is a standalone service running on a separate node. In simple terms, this is also called an agent. The XRegion Service is deployed when you are connecting the local data store with a remote data store to create a multi-region table.