Define The Consistency Levels For Read Operations In Cassandra.?

1.	Define The Consistency Levels For Read Operations In Cassandra.?
Answer» ALL: HIGHLY consistent. A write must be written to commitlog and memtable on all replica nodes in the cluster EACH_QUORUM: A write must be written to commitlog and memtable on QUORUM of replica nodes in all data CENTERS. LOCAL_QUORUM:A write must be written to commitlog and memtable on quorum of replica nodes in the same center. ONE: A write must be written to commitlog and memtableof at least one replica node. TWO, Three: Same as One but at least two and three replica nodes, respectively LOCAL_ONE: A write must be written for at least one replica node in the LOCAL data center ANY SERIAL: Linearizable CONSISTENCY to prevent unconditional updates LOCAL_SERIAL: Same as Serial but restricted to local data center

Answer»

ALL: HIGHLY consistent. A write must be written to commitlog and memtable on all replica nodes in the cluster
EACH_QUORUM: A write must be written to commitlog and memtable on QUORUM of replica nodes in all data CENTERS.
LOCAL_QUORUM:A write must be written to commitlog and memtable on quorum of replica nodes in the same center.
ONE: A write must be written to commitlog and memtableof at least one replica node.
TWO, Three: Same as One but at least two and three replica nodes, respectively
LOCAL_ONE: A write must be written for at least one replica node in the LOCAL data center ANY
SERIAL: Linearizable CONSISTENCY to prevent unconditional updates
LOCAL_SERIAL: Same as Serial but restricted to local data center

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