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https://issues.apache.org/jira/browse/CASSANDRA-2774?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13049771#comment-13049771
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Yang Yang commented on CASSANDRA-2774:
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--- "the only valid answer...." not really
In fact this is the same reasoning that I explained in your
Net partition case on gmail.g list
You expect that it is" the only valid" case* *
Because* ** of assumed timing order from client respective
but we know that timing
Is not trustworthy and this order on client is
Not respected because client does not participate
In the logical clock protocol of epoch generation
Btw we'd better force ROW for delete so we achieve
Faster agreement and lose fewer adds
On old epoch.
I think with quorum delete you will guarantee
timing to be consistent eoyh client
And then achieve client expected result I. Your
Case, id like to hear your counter example
Pardon the typing, on phone, will be
On computer soon
> one way to make counter delete work better
> ------------------------------------------
>
> Key: CASSANDRA-2774
> URL: https://issues.apache.org/jira/browse/CASSANDRA-2774
> Project: Cassandra
> Issue Type: New Feature
> Affects Versions: 0.8.0
> Reporter: Yang Yang
> Attachments: counter_delete.diff
>
>
> current Counter does not work with delete, because different merging order of
> sstables would produces different result, for example:
> add 1
> delete
> add 2
> if the merging happens by 1-2, (1,2)--3 order, the result we see will be 2
> if merging is: 1--3, (1,3)--2, the result will be 3.
> the issue is that delete now can not separate out previous adds and adds
> later than the delete. supposedly a delete is to create a completely new
> incarnation of the counter, or a new "lifetime", or "epoch". the new approach
> utilizes the concept of "epoch number", so that each delete bumps up the
> epoch number. since each write is replicated (replicate on write is almost
> always enabled in practice, if this is a concern, we could further force ROW
> in case of delete ), so the epoch number is global to a replica set
> changes are attached, existing tests pass fine, some tests are modified since
> the semantic is changed a bit. some cql tests do not pass in the original
> 0.8.0 source, that's not the fault of this change.
> see details at
> http://mail-archives.apache.org/mod_mbox/cassandra-user/201106.mbox/%3cbanlktikqcglsnwtt-9hvqpseoo7sf58...@mail.gmail.com%3E
> the goal of this is to make delete work ( at least with consistent behavior,
> yes in case of long network partition, the behavior is not ideal, but it's
> consistent with the definition of logical clock), so that we could have
> expiring Counters
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