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A comment on Cassandra is not row level consistent. Parent comment

Re:Cassandra is not row level consistent by im_down_w_otp on Thursday November 24, 2016 @11:27PM (#13034409)
Quorum won't solve consistency problems like this unless you can also guarantee a serialized reader/writer for any given piece of data. The best you can do by pinning queries to primary replicas and enforcing R + W > N is RYOW consistency, and that depends on the aforementioned serialization point.
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Re:Cassandra is not row level consistent by pkolaczk on Friday November 25, 2016 @07:52AM (#13036360)
Quorum reads + writes and applying non-destructive updates only are enough to get linearizabile consistency in Cassandra, even if clocks are not perfectly synchronized.
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Re:Cassandra is not row level consistent by im_down_w_otp on Friday November 25, 2016 @09:53PM (#13041433)
If you're applying non-destructive updates then you don't even need quorum to achieve consistency. You're just writing immutable data.
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Re:Cassandra is not row level consistent by pkolaczk on Saturday November 26, 2016 @04:30AM (#13042694)
If you're applying non-destructive updates without quorum, you would not get monotonic read consistency, because stale reads would be possible. You could write a row, immediately read it back from another replica and find out the row is not there, because that replica didn't get it yet. You'd have only eventual consistency.
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