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I read that writes are wriiten to any node in the cluster. aren't they supposed to be written where the partition key is hashed so that retrieval is efficent ? again how replication ensures efficient retrival if same data is found on multiple nodes ? Lots of confusion !!
I took reference from here :
Pls suggest
There are 2 things:
To make queries efficient, 1 & 2 should be the same - so it's a job for a client to send request to the coordinating node that is also a replica. Inside a driver this is a job for load balancing policy - by default it's a "token-aware" - this means that it's able to calculate a token and identify the replicas to which query need to be sent (please note that in drivers, token aware routing happens only for prepared queries). You can read more about token-aware routing in Java driver documentation or in the developing with drivers guide.
Thanks !! but if same data is replicated to one or more nodes that means 1 partition key exists in one or more node so in that case when we say we store on basis of hash value how does that happen?
@pranali.khanna101994_189965, here are couple additional resources to help you understand the token ranges and its allocation algorithms,
nodetool getendpoints command
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