Cassandra

Apache Cassandra is an highly available ( fault tolerant) ,  linearly scalable ( allows adding nodes with limited overhead , uses consistent hashing ) , high performance ( because it can be scalable  ) , NoSQL ( key/value based ) , distributed database. It is designed on Dynamo principles (incremental scalability - , symmetry - every node is same, decentralization - peer to peer interaction , Heterogeneity -  allow heterogeneous infrastructure)  and follows "column family" ( Google BigTable ) data modeling.  It uses gossip protocol.

In cassandra data is partitioned by a multi-column primary key that gets a hash value and is sent to the node whose token is numerically bigger than the hash value. 






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