cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From DuyHai Doan <doanduy...@gmail.com>
Subject Re: group by select queries
Date Thu, 01 Feb 2018 13:08:10 GMT
Worth digging into the source code of GROUP BY but as far as I remember,
using GROUP BY without any aggregation function will lead to C* picking
just the first row (or maybe last, not sure on this point) row at hand.

About ordering, since the grouping is on a component of partition key, do
not expect any sensible order since only token order matters

On Thu, Feb 1, 2018 at 6:38 AM, kurt greaves <kurt@instaclustr.com> wrote:

> Seems problematic. Would you be able to create a JIRA ticket with the
> above information/examples?
>
> On 30 January 2018 at 22:41, Modha, Digant <Digant.Modha@tdsecurities.com>
> wrote:
>
>> It was local quorum.  There’s no difference with CONSISTENCY ALL.
>>
>>
>>
>> Consistency level set to LOCAL_QUORUM.
>>
>> cassandra@cqlsh> select * from wp.position  where account_id = 'user_1';
>>
>>
>>
>> account_id | security_id | counter | avg_exec_price | pending_quantity |
>> quantity | transaction_id | update_time
>>
>> ------------+-------------+---------+----------------+------
>> ------------+----------+----------------+-------------------
>> --------------
>>
>>      user_1 |        AMZN |       2 |         1239.2 |                0
>> |     1011 |           null | 2018-01-25 17:18:07.158000+0000
>>
>>      user_1 |        AMZN |       1 |         1239.2 |                0
>> |     1010 |           null | 2018-01-25 17:18:07.158000+0000
>>
>>
>>
>> (2 rows)
>>
>> cassandra@cqlsh> select * from wp.position  where account_id = 'user_1'
>> group by security_id;
>>
>>
>>
>> account_id | security_id | counter | avg_exec_price | pending_quantity |
>> quantity | transaction_id | update_time
>>
>> ------------+-------------+---------+----------------+------
>> ------------+----------+----------------+-------------------
>> --------------
>>
>>      user_1 |        AMZN |       1 |         1239.2 |                0
>> |     1010 |           null | 2018-01-25 17:18:07.158000+0000
>>
>>
>>
>> (1 rows)
>>
>> cassandra@cqlsh> select account_id,security_id, counter,
>> avg_exec_price,quantity, update_time from wp.position  where account_id =
>> 'user_1' group by security_id ;
>>
>>
>>
>> account_id | security_id | counter | avg_exec_price | quantity |
>> update_time
>>
>> ------------+-------------+---------+----------------+------
>> ----+---------------------------------
>>
>>      user_1 |        AMZN |       2 |         1239.2 |     1011 |
>> 2018-01-25 17:18:07.158000+0000
>>
>>
>>
>> (1 rows)
>>
>> cassandra@cqlsh>  consistency all;
>>
>> Consistency level set to ALL.
>>
>> cassandra@cqlsh> select * from wp.position  where account_id = 'user_1'
>> group by security_id;
>>
>>
>>
>> account_id | security_id | counter | avg_exec_price | pending_quantity |
>> quantity | transaction_id | update_time
>>
>> ------------+-------------+---------+----------------+------
>> ------------+----------+----------------+-------------------
>> --------------
>>
>>      user_1 |        AMZN |       1 |         1239.2 |                0
>> |     1010 |           null | 2018-01-25 17:18:07.158000+0000
>>
>>
>>
>> (1 rows)
>>
>> cassandra@cqlsh> select account_id,security_id, counter,
>> avg_exec_price,quantity, update_time from wp.position  where account_id =
>> 'user_1' group by security_id ;
>>
>>
>>
>> account_id | security_id | counter | avg_exec_price | quantity |
>> update_time
>>
>> ------------+-------------+---------+----------------+------
>> ----+---------------------------------
>>
>>      user_1 |        AMZN |       2 |         1239.2 |     1011 |
>> 2018-01-25 17:18:07.158000+0000
>>
>>
>>
>>
>>
>> *From:* kurt greaves [mailto:kurt@instaclustr.com]
>> *Sent:* Monday, January 29, 2018 11:03 PM
>> *To:* User
>> *Subject:* Re: group by select queries
>>
>>
>>
>> What consistency were you querying at? Can you retry with CONSISTENCY ALL?
>>
>>
>>
>> ​
>>
>>
>> TD Securities disclaims any liability or losses either direct or
>> consequential caused by the use of this information. This communication is
>> for informational purposes only and is not intended as an offer or
>> solicitation for the purchase or sale of any financial instrument or as an
>> official confirmation of any transaction. TD Securities is neither making
>> any investment recommendation nor providing any professional or advisory
>> services relating to the activities described herein. All market prices,
>> data and other information are not warranted as to completeness or accuracy
>> and are subject to change without notice Any products described herein are
>> (i) not insured by the FDIC, (ii) not a deposit or other obligation of, or
>> guaranteed by, an insured depository institution and (iii) subject to
>> investment risks, including possible loss of the principal amount invested.
>> The information shall not be further distributed or duplicated in whole or
>> in part by any means without the prior written consent of TD Securities. TD
>> Securities is a trademark of The Toronto-Dominion Bank and represents TD
>> Securities (USA) LLC and certain investment banking activities of The
>> Toronto-Dominion Bank and its subsidiaries.
>>
>
>

Mime
View raw message