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From Anthony John <chirayit...@gmail.com>
Subject Re: for counters: does read have to be ALL ?
Date Thu, 03 Feb 2011 23:02:45 GMT
>From the architecture section of wiki. And it makes sense!

More specifically: R=read replica count W=write replica count N=replication
factor Q=*QUORUM* (Q = N / 2 + 1)

   -

   If W + R > N, you will have consistency
   - W=1, R=N
   - W=N, R=1
   - W=Q, R=Q where Q = N / 2 + 1


On Thu, Feb 3, 2011 at 3:39 PM, Yang <teddyyyy123@gmail.com> wrote:

> the pdf at the design doc
>
> https://issues.apache.org/jira/secure/attachment/12459754/Partitionedcountersdesigndoc.pdf
>
> does say so:
> page 2 "- strongly consistent read: requires consistency level ALL.
> (QUORUM is insufficient.)
> "
>
> but the wiki  http://wiki.apache.org/cassandra/Counters
> gave a code example:
>
> rv = client.get_counter('key1', ColumnPath(column_family='Counter1',
> column='c1'), ConsistencyLevel.ONE)
>
>
> is one of them wrong?
>
> Thanks
> Yang
>

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