Data distribution and replication
In DataStax Enterprise (DSE), data distribution and replication go together. DSE organizes data by table and uses a primary key to identify unique records, helping determine the node on which to store data. Replicas are copies of rows stored on multiple nodes to ensure reliability and fault tolerance. A replica also refers to data first written. All replicas are equally important; there is no primary replica.
Learn the important concept of how the data is distributed to the nodes in a cluster.
Features affecting replication include:
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Replication strategy determines the replicas for each row of data.
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Virtual nodes assign data ownership to physical machines.
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Partitioners distribute the data across the cluster.
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Snitches define the topology information that the replication strategy uses to place replicas.