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From Data Craftsman <database.crafts...@gmail.com>
Subject Re: Is this possible.
Date Thu, 26 Apr 2012 20:44:04 GMT
DML example,

insert into user_score_v3(name, highscore, x,y,z)
values ('abc', 299.76, 1001, '*', '*');
...


2012/4/26 Data Craftsman <database.craftsman@gmail.com>:
> Data model:
>
> REM CQL 3.0
> ----
>
> $> cqlsh --cql3
>
> drop COLUMNFAMILY user_score_v3;
>
> CREATE COLUMNFAMILY user_score_v3
> (name varchar,
>  highscore float,
>  x int,
>  y varchar,
>  z varchar,
>  PRIMARY KEY (name, highscore)
> );
>
> DML is as usual, as commom, as RDBMS SQL.
>
> Query:
>
> Top 3,
>
> SELECT name, highscore, x,y,z FROM user_score_v3 where name='abc'
> ORDER BY highscore desc
> LIMIT 3;
>
> You may try Reversed Comparators, see
> http://thelastpickle.com/2011/10/03/Reverse-Comparators/
>
> Help this is helpful.
>
> Thank,
> Charlie | DBA
>
>
> On Thu, Apr 26, 2012 at 12:34 PM, Ed Jone <edjone6@gmail.com> wrote:
>> Hello,
>>
>> I am new to cassandra and was hoping if someone can tell me if the following
>> is possible.
>>
>>
>> Given I have a columnfamily with a list of users in each Row.
>>
>> Each user has the properties: name, highscore, x, y, z.
>>
>> I want to use name as the column key, but I want the columns to be sorted by
>> highscore (always).
>>
>> The only reads would be to get the top N users by highscore in a given row.
>> I thought about adding the weight to the name as the key (eg:
>> 299.76-johnsmith) but then I would not be able to update a given user.
>>
>> This was not possible in the past, but I am not familiar, with the newer
>> cassandra versions.
>
>
> --
> Thanks,
>
> Charlie (@mujiang) 一个 木匠
> =======
> Data Architect Developer
> http://mujiang.blogspot.com



-- 
--
Thanks,

Charlie (@mujiang) 一个 木匠
=======
Data Architect Developer
http://mujiang.blogspot.com

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