Re: Sorted group by
| От | Thom Brown |
|---|---|
| Тема | Re: Sorted group by |
| Дата | |
| Msg-id | AANLkTikaYYY0xftv=1nqPQZWbqiqyOgaSLz69cV_OcMo@mail.gmail.com обсуждение исходный текст |
| Ответ на | Re: Sorted group by (Matthew Wakeling <matthew@flymine.org>) |
| Ответы |
Re: Sorted group by
|
| Список | pgsql-performance |
On 10 August 2010 17:03, Matthew Wakeling <matthew@flymine.org> wrote: > On Tue, 10 Aug 2010, Thomas Kellerer wrote: >> >> No. It's built in (8.4) and it's called Windowing functions: >> http://www.postgresql.org/docs/8.4/static/tutorial-window.html >> http://www.postgresql.org/docs/8.4/static/functions-window.html >> >> SELECT group, last_value(value) over(ORDER BY number) >> FROM table > > I may be mistaken, but as I understand it, a windowing function doesn't > reduce the number of rows in the results? > I think you are mistaken. The last_value function is a window function aggregate. Give it a try. -- Thom Brown Registered Linux user: #516935
В списке pgsql-performance по дате отправления: