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From Tyler Hobbs <ty...@riptano.com>
Subject Re: I have TimeUUID sorted keys. Can I get the range query return rows in the same order as sorted keys?
Date Mon, 27 Dec 2010 17:45:35 GMT
Might as well link to this nice article for any discussions of OPP vs RP:

http://ria101.wordpress.com/2010/02/22/cassandra-randompartitioner-vs-orderpreservingpartitioner/

- Tyler

On Mon, Dec 27, 2010 at 11:18 AM, Narendra Sharma <narendra.sharma@gmail.com
> wrote:

> You will need to use OPP to perform range scans. Look for Range Queries on
> http://wiki.apache.org/cassandra/DataModel
>
> Look at this to understand why range queries are not supported for
> RamdomPartitioner (https://issues.apache.org/jira/browse/CASSANDRA-1750)
>
> Thanks,
> Naren
>
>
> On Mon, Dec 27, 2010 at 8:35 AM, Roshan Dawrani <roshandawrani@gmail.com>wrote:
>
>> I had seen RangeSlicesQuery, but I didn't notice that I could also give a
>> key range there.
>>
>> How does a KeyRange work? Doesn't it need some sort from the partitioner -
>> whether that is order preserving or not?
>>
>> I couldn't be sure of a query that was based on order of the rows in the
>> column family, so I didn't explore that much.
>>
>>
>>
>> On Mon, Dec 27, 2010 at 9:55 PM, Narendra Sharma <
>> narendra.sharma@gmail.com> wrote:
>>
>>> Did you look at get_range_slices? Once you get the columns from super
>>> column, pick the first and last to form the range and fire the
>>> get_range_slice.
>>>
>>> Thanks,
>>> -Naren
>>>
>>>
>>> On Mon, Dec 27, 2010 at 6:12 AM, Roshan Dawrani <roshandawrani@gmail.com
>>> > wrote:
>>>
>>>> This silly question is retrieved back with apology. There couldn't be
>>>> anything easier to handle at the application level.
>>>>
>>>> rgds,
>>>> Roshan
>>>>
>>>>
>>>> On Mon, Dec 27, 2010 at 9:04 AM, Roshan Dawrani <
>>>> roshandawrani@gmail.com> wrote:
>>>>
>>>>> Hi,
>>>>> I have the following 2 column families - one being used to store full
>>>>> rows for an entity and other is an index table for having the TimeUUID
>>>>> sorted row keys.
>>>>>
>>>>> I am able to query the TimeUUID columns under the super column fine.
>>>>> But now I need to go to main CF and get the data and I want the rows
in the
>>>>> same time order as the keys.
>>>>>
>>>>> I am using MultiGetSliceQuery to query the main entity data for the
>>>>> sorted keys, but the rows don't come back in the same order, which defeats
>>>>> the purpose of storing the time sorted subcolumns. I suppose for each
key, I
>>>>> can fire an individual SliceQuery, but that does not look efficient to
me. I
>>>>> do want to fire a range query.
>>>>>
>>>>> MainEntityCF {
>>>>>          TimeUUIDKeyA: ["Col1" : "Val1", "Col2" : "Val2", "Col3" :
>>>>> "Val3"]
>>>>>          TimeUUIDKeyX: ["Col1" : "Val1", "Col2" : "Val2", "Col3" :
>>>>> "Val3"]
>>>>>          TimeUUIDKeyB: ["Col1" : "Val1", "Col2" : "Val2", "Col3" :
>>>>> "Val3"]
>>>>>          TimeUUIDKeyY: ["Col1" : "Val1", "Col2" : "Val2", "Col3" :
>>>>> "Val3"]
>>>>> }
>>>>> MainEntityCF_Index {
>>>>>       "SomeSuperColumn": [TimeUUIDKeyA:null, TimeUUIDKeyB:null,
>>>>> TimeUUIDKeyX:null, TimeUUIDKeyY:null]
>>>>> }
>>>>>
>>>>> --
>>>>> Roshan
>>>>> Blog: http://roshandawrani.wordpress.com/
>>>>> Twitter: @roshandawrani <http://twitter.com/roshandawrani>
>>>>> Skype: roshandawrani
>>>>>
>>>>>
>>>
>>
>>
>> --
>> Roshan
>> Blog: http://roshandawrani.wordpress.com/
>> Twitter: @roshandawrani <http://twitter.com/roshandawrani>
>> Skype: roshandawrani
>>
>>
>

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