Re: wip: functions median and percentile

Поиск
Список
Период
Сортировка
От Hitoshi Harada
Тема Re: wip: functions median and percentile
Дата
Msg-id AANLkTi=-cKHt8i8DqEHTpd3p1PApLX1Mt37J5VV9v973@mail.gmail.com
обсуждение исходный текст
Ответ на Re: wip: functions median and percentile  (Pavel Stehule <pavel.stehule@gmail.com>)
Ответы Re: wip: functions median and percentile  (Pavel Stehule <pavel.stehule@gmail.com>)
Re: wip: functions median and percentile  (Tom Lane <tgl@sss.pgh.pa.us>)
Список pgsql-hackers
2010/9/26 Pavel Stehule <pavel.stehule@gmail.com>:
> Hello,
>
> there is updated version - with support of window clause. The limits
> are work_mem for using inside window aggregate or unlimited when it is
> used as standard query.
>
> This patch needs a few work - can share a compare functionality with
> tuplesort.c, but I would to verify a concept now.
>
> Comments?

Sorry for delay. I read the patch and it seems the result is sane. For
window function calls, I agree that the current tuplesort is not
enough to implement median functions and the patch introduces its own
memsort mechanism, although memsort has too much copied from
tuplesort. It looks to me not so difficult to modify the existing
tuplesort to guarantee staying in memory always if an option to do so
is specified from caller. I think that option can be used by other
cases in the core code.

Regards,


-- 
Hitoshi Harada


В списке pgsql-hackers по дате отправления:

Предыдущее
От: Magnus Hagander
Дата:
Сообщение: Re: Using streaming replication as log archiving
Следующее
От: Leonardo Francalanci
Дата:
Сообщение: Re: I: About "Our CLUSTER implementation is pessimal" patch