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From "Hiller, Dean" <Dean.Hil...@nrel.gov>
Subject Re: What does ReadRepair exactly do?
Date Wed, 24 Oct 2012 11:51:51 GMT
Keep in mind, returning the older version is usually fine.  Just imagine
if your user clicked write 1 ms before, then the new version might be
returned.  If he gets the older version and refreshes the page, he gets
the newer version.  Same with an automated program as wellÅ .in general it
is okay to get the older or newer value.  If you are reading 2 rows
however instead of one, that may change.

Dean

On 10/23/12 7:04 PM, "shankarpnsn" <shankarpnsn@gmail.com> wrote:

>manuzhang wrote
>> why repair again? We block until the consistency constraint is met. Then
>> the latest version is returned and repair is done asynchronously if any
>> mismatch. We may retry read if fewer columns than required are returned.
>
>Just to make sure I understand you correct, considering the case when a
>read
>repair is in flight and a subsequent write affects one or more of the
>replicas that was scheduled to received the repair mutations. In this
>case,
>are you saying that we return the older version to the user rather than
>the
>latest version that was effected by the write ?
>
>
>
>--
>View this message in context:
>http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/What-does
>-ReadRepair-exactly-do-tp7583261p7583355.html
>Sent from the cassandra-user@incubator.apache.org mailing list archive at
>Nabble.com.


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