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Cristian Opris commented on CASSANDRA-5062: ------------------------------------------- Jonathan, how do you plan fitting CAS into Paxos ? Paxos would give consensus, but what would the consesus be on ? The value to write ? Is the CAS run at each replica or just the proposer ? How do you make sure when you run CAS locally you have actually learned the *previous* consensus value (to compare expected with) ? > Support CAS > ----------- > > Key: CASSANDRA-5062 > URL: https://issues.apache.org/jira/browse/CASSANDRA-5062 > Project: Cassandra > Issue Type: New Feature > Components: API, Core > Reporter: Jonathan Ellis > Fix For: 2.0 > > > "Strong" consistency is not enough to prevent race conditions. The classic > example is user account creation: we want to ensure usernames are unique, so > we only want to signal account creation success if nobody else has created > the account yet. But naive read-then-write allows clients to race and both > think they have a green light to create. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira