Re: Help with SQL staterment
От
Thom Brown
Тема
Re: Help with SQL staterment
Дата
Msg-id
BANLkTin2xvC1PZebXO3XD8YNXzPtmYoE3w@mail.gmail.com
Ответ на
Re: Help with SQL staterment (Chris Campbell)
Список
Дерево обсуждения
Help with SQL staterment Chris Campbell <ccampbell@cascadeds.com>
Re: Help with SQL staterment Steve Crawford <scrawford@pinpointresearch.com>
Re: Help with SQL staterment Thom Brown <thom@linux.com>
Re: Help with SQL staterment Chris Campbell <ccampbell@cascadeds.com>
Re: Help with SQL staterment Thom Brown <thom@linux.com>
Re: Help with SQL staterment Steve Crawford <scrawford@pinpointresearch.com>
Re: Help with SQL staterment Thom Brown <thom@linux.com>
Re: Help with SQL staterment Chris Campbell <ccampbell@cascadeds.com>
problem "Phillip B Childs" <it@marisusa.com>
Re: problem Richard Broersma <richard.broersma@gmail.com>
On 30 June 2011 23:25, Chris Campbell wrote:
>>It should look something like this:
>
>>SELECT contactkey, max(paymentdate)
>>FROM my_table
>>GROUP BY contactkey;
>
> Yeah, that's what I started with. The problem is that I "need" the payment key returned in addition to the other fields based on the max(paymentdate). When I add paymentkey to the mix I keep ending up with a cartesianed product showing multiple paymentkeys.
You can try this:
SELECT DISTINCT ON (contactkey)
paymentkey, contactkey, paymentdate
FROM
my_table
ORDER BY
contactkey, paymentdate DESC
--
Thom Brown
Twitter: @darkixion
IRC (freenode): dark_ixion
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