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From Narendra Sharma <narendra.sha...@gmail.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 17:18:23 GMT
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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