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From Sorin Manolache <sor...@gmail.com>
Subject Re: is the select result grouped by the value of the partition key?
Date Fri, 12 Apr 2013 07:24:28 GMT
On 2013-04-11 22:10, aaron morton wrote:
>> Is it guaranteed that the rows are grouped by the value of the
>> partition key? That is, is it guaranteed that I'll get
> Your primary key (k1, k2) is considered in type parts (partition_key ,
> grouping_columns). In your case the primary_key is key and the grouping
> column in k2. Columns are ordered by the grouping columns, k2.
>
> See http://thelastpickle.com/2013/01/11/primary-keys-in-cql/

Thank you for the answer.

However my question was about the _grouping_ (not ordering) of _rows_ 
(not columns).

Sorin

>
> Cheers
>
> -----------------
> Aaron Morton
> Freelance Cassandra Consultant
> New Zealand
>
> @aaronmorton
> http://www.thelastpickle.com
>
> On 12/04/2013, at 3:19 AM, Sorin Manolache <sorinm@gmail.com
> <mailto:sorinm@gmail.com>> wrote:
>
>> Hello,
>>
>> Let us consider that we have a table t created as follows:
>>
>> create table t(k1 vachar, k2 varchar, value varchar, primary key (k1,
>> k2));
>>
>> Its contents is
>>
>> a m x
>> a n y
>> z 0 9
>> z 1 8
>>
>> and I perform a
>>
>> select * from p where k1 in ('a', 'z');
>>
>> Is it guaranteed that the rows are grouped by the value of the
>> partition key? That is, is it guaranteed that I'll get
>>
>> a m x
>> a n y
>> z 0 9
>> z 1 8
>>
>> or
>>
>> a n y
>> a m x
>> z 1 8
>> z 0 9
>>
>> or even
>>
>> z 0 9
>> z 1 8
>> a n y
>> a m x
>>
>> but NEVER
>>
>> a m x
>> z 0 9
>> a n y
>> z 1 8
>>
>>
>> Thank you,
>> Sorin
>


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