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Anchor(clocktie)
== What happens if two updates are made with the same timestamp? ==
- Updates must be commutative, since they may arrive in different orders on
different replicas. Thus, in the case of a timestamp tie, Cassandra follows
two rules: first, deletes take precedence over inserts/updates. Second, if
there are two updates, the one with the lexically larger value is selected.
+ Updates must be commutative, since they may arrive in different orders on
different replicas. As long as Cassandra has a deterministic way to pick the
winner, the one selected is as valid as any other, and the specifics should be
treated as an implementation detail. That said, in the case of a timestamp
tie, Cassandra follows two rules: first, deletes take precedence over
inserts/updates. Second, if there are two updates, the one with the lexically
larger value is selected.
