ok got it. So, only using LWT txn the updates across nodes for a particular row can be isolated, so basically paxos would ensure serializable isolation
Thanks, Rajesh On Wed, May 16, 2018 at 4:56 PM, kurt greaves <k...@instaclustr.com> wrote: > Atomicity and isolation are only guaranteed within a replica. If you have > multiple concurrent requests across replicas last timestamp will win. You > can get better isolation using LWT which uses paxos under the hood. > > On 16 May 2018 at 08:55, Rajesh Kishore <rajesh10si...@gmail.com> wrote: > >> Hi, >> >> I am just curious to know when Cassandra doc says the atomicity and >> isolation is guaranteed for a row. >> Does it mean, two requests updating a row- "R1" at different replica will >> be candidate for atomicity and isolation? >> >> For instance , I have a setup where RF is 2 >> I have a client application where two requests of updating a particular >> row #R1 goes to two coordinator nodes at same time. >> Row "R1" has presence in nodes - N1, N2 (since RF is 2) >> Does Cassandra ensure atomicity & isolation across replicas/partition for >> a particular row? If so , then how does it get handled does Cassandra >> follows 2 Phase commit txn for a row or Cassandra uses distributed lock for >> a row? >> >> Thanks, >> Rajesh >> >> >> >
