Hi Daniel, What is the RF and CL for Delete?Are you using asynchronous writes?Are you firing both statements from same node sequentially?Are you firing these queries in a loop such that more than one delete and LWT is fired for same partition? I think if you have the same client executing both statements sequentially in same thread i.e. one after another and delete is synchronous, it should work fine. LWT will be executed after Cassandra has written on Quorum of nodes and will see the data. Paxos of LWT shall only be initiated when delete completes. I think, LWT should not be mixed with normal write when you have such writes fired from multiple nodes/threads on the same partition.
ThanksAnuj Sent from Yahoo Mail on Android On Tue, 10 Oct 2017 at 14:10, Daniel Woo<daniel.y....@gmail.com> wrote: The document explains you cannot mix themhttp://docs.datastax.com/en/archived/cassandra/2.2/cassandra/dml/dmlLtwtTransactions.html But what happens under the hood if I do? e.g, DELETE ....INSERT ... IF NOT EXISTS The coordinator has 4 steps to do the second statement (INSERT)1. prepare/promise a ballot2. read current row from replicas3. propose new value along with the ballot to replicas4. commit and wait for ack from replicas My question is, once the row is DELETed, the next INSERT LWT should be able to see that row's tombstone in step 2, then successfully inserts the new value. But my tests shows that this often fails, does anybody know why? -- Thanks & Regards, Daniel
