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From Wojciech Kaczmarek <kaczmare...@gmail.com>
Subject Re: Question about Token selection for order-preserving partitioner
Date Tue, 16 Feb 2010 16:45:01 GMT
Hi!

My comment was supposed to mean that you don't use TimeUUIDType as a token
because it's a possible column type, not a key type (at least is what I know
from a wiki and my short experience, I didn't check the source). You've
probably mistaken sorting of different columns within a row (which depends
on a type of column) with sorting of your keys which is possible when using
order-preserving partitioner. The sorting of keys seems to depend only on a
specific partitioner class used in config.

Application-specific keys distribution means that you should predict how
your keys will be generated in order to set seeds for your nodes. If you're
in doubt and this is your test environment you could just leave InitialToken
empty.

It would help if you told us what the semantics of your keys are.

2010/2/16 Nguyễn Minh Kha <nminhkha@gmail.com>

> Hi!
>
> I think, my question is not clearly.
>
> I don't know to config these nodes for this cluster. I want to use
> TimeUUIDType and order-preserving partitioner for range query.
> How to config InitialToken and seeds for node01, node02, node03.
>
> I see the wiki topic Operations explain InitialToken for order-preserving
> partitioner:
>
> [With order preserving partioners, your key distribution will be
> application-dependent. You should still take your best guess at specifying
> initial tokens (guided by sampling actual data, if possible), but you will
> be more dependent on active load balancing (see below) and/or adding new
> nodes to hot spots.]'
>
> I don't know [application-dependent]. And I don't know config seeds section
> every node.
>
> Sorry for my english.
>
>
> On Tue, Feb 16, 2010 at 7:58 PM, Wojciech Kaczmarek <kaczmarek.w@gmail.com
> > wrote:
>
>> Hi!
>>
>> 2010/2/16 Nguyễn Minh Kha <nminhkha@gmail.com>
>>
>>
>>> I read the wiki topic Operations<http://wiki.apache.org/cassandra/Operations>and
I don't understant way to use Token selection for order-preserving
>>> partitioner (application-dependent).
>>> I want create blog comment use TimeUUIDType and order-preserving for
>>> range query, this cluster run in 3 nodes.
>>>
>>>
>> How to add token, config seeds and more to run this cluster?
>>>
>>> Thank very much.
>>>
>>
>> The order-preserving partitioner will use keys as tokens. The type you're
>> talking about could be the column type but that's another thing.
>>
>>
>

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