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From prasenjit mukherjee <prasen....@gmail.com>
Subject Re: random partitioner and key scan
Date Thu, 19 Jul 2012 16:46:16 GMT
When a request for token change is issued ( via nodetool ) then on
what basis a node will move some of its rows to other node, as there
will be no way to scan rows based on MD5 hash in a given node ( if the
keys are not prefixed with MD5 hash )

On Thu, Jul 19, 2012 at 1:43 PM, Patrik Modesto
<patrik.modesto@gmail.com> wrote:
> Hi Prasenjit,
>
> I don't see the need to recalculate anything. One key has a one MD5
> hash, it doesn't change. Just use the hash to select a node, than just
> the plain key. Can you elaborate on the redistribution please?
>
> Regards,
> P.
>
> On Thu, Jul 19, 2012 at 9:09 AM, prasenjit mukherjee
> <prasen.bea@gmail.com> wrote:
>> The probem could be while redistributing the tokens. In that case the
>> hashes has to be recalculated on each fo the candidate node.
>>
>> -Thanks,
>> Prasenjit
>>
>> On Thu, Jul 19, 2012 at 12:19 PM, Patrik Modesto
>> <patrik.modesto@gmail.com> wrote:
>>> Hi,
>>>
>>> I know that RandomPartitioner does MD5 of a key and the MD5 is then
>>> used for key distribution AND key ordering. I was just wondering if
>>> it's possible to have RandomPartitioner just for key distribution and
>>> OrderedPartitioner just for per-node key ordering. That would solve
>>> the often requested key scan feature.
>>>
>>> Regards,
>>> Patrik

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