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From Shinpei Ohtani <shinpei.oht...@gmail.com>
Subject Re: key is sorted?
Date Sun, 09 May 2010 12:25:17 GMT
Hi,

> If you use random partitioning, you can loop through all keys with a range
> query, but they will not be sorted.
>
> True or False?

I think they will be sorted in a way of MD5 hash if you use RandomPartitioner,
at least I looked into SSTables and RandomPartitioner#getToken.

On Sun, May 9, 2010 at 4:00 PM, David Boxenhorn <david@lookin2.com> wrote:
> This is something that I'm not sure that I understand. Can somebody
> confirm/deny that I understand it? Thanks.
>
> If you use random partitioning, you can loop through all keys with a range
> query, but they will not be sorted.
>
> True or False?
>
> On Sat, May 8, 2010 at 3:45 AM, AJ Chen <ajchen@web2express.org> wrote:
>>
>> thanks, that works. -aj
>>
>> On Fri, May 7, 2010 at 1:17 PM, Stu Hood <stu.hood@rackspace.com> wrote:
>>>
>>> Your IPartitioner implementation decides how the row keys are sorted: see
>>> http://wiki.apache.org/cassandra/StorageConfiguration#Partitioner . You need
>>> to be using one of the OrderPreservingPartitioners if you'd like a
>>> reasonable order for the keys.
>>>
>>> -----Original Message-----
>>> From: "AJ Chen" <ajchen@web2express.org>
>>> Sent: Friday, May 7, 2010 3:10pm
>>> To: user@cassandra.apache.org
>>> Subject: key is sorted?
>>>
>>> I have a super column family for "topic", key being the name of the
>>> topic.
>>> <ColumnFamily Name="Topic" CompareWith="UTF8Type" ColumnType="Super"
>>> CompareSubcolumnsWith="BytesType" />
>>> When I retrieve the rows, the rows are not sorted by the key. Is the row
>>> key
>>> sorted in cassandra by default?
>>>
>>> -aj
>>> --
>>> AJ Chen, PhD
>>> Chair, Semantic Web SIG, sdforum.org
>>> http://web2express.org
>>> twitter @web2express
>>> Palo Alto, CA, USA
>>>
>>>
>>
>>
>>
>> --
>> AJ Chen, PhD
>> Chair, Semantic Web SIG, sdforum.org
>> http://web2express.org
>> twitter @web2express
>> Palo Alto, CA, USA
>
>



-- 
=============================
Shinpei Ohtani
mail    : shinpei.ohtani@gmail.com
blog    : http://d.hatena.ne.jp/shot6/
twitter : http://twitter.com/shot6
=============================

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