Re: Calculate the ratio

Поиск
Список
Период
Сортировка
От msi77
Тема Re: Calculate the ratio
Дата
Msg-id 765121313413237@web108.yandex.ru
обсуждение исходный текст
Ответ на Calculate the ratio  (Andreas Forø Tollefsen <andreasft@gmail.com>)
Список pgsql-sql
Hi,

Try this

select gridyear, gwcode, sum(case when cf=1 then area else o end) as cf1,
sum(case when cf=0 then area else 0 end)  as cf0
from table
group by gridyear, gwcode

http://sql-ex.ru/help/select8.php#case

15.08.2011, 16:21, "Andreas Forø Tollefsen" <andreasft@gmail.com>:
> Hi all,
>
> This is probably quite simple. I want to calculate the ratio of each country (gwcode) which experiences a 1 in one
column(cf).
 
>
> Structure:
>
> gid; gridyear; gwcode; area; cf
>
> I want to select the SUM(area) WHERE cf = 1 into one column, and SUM(area) WHERE cf = 0 into another column and group
bygridyear and gwcode.
 
> Then i can see the ratio of the area of each country affected by cf.
>
> Any suggestions?
>
> Thanks.
>
> A.


В списке pgsql-sql по дате отправления:

Предыдущее
От: Andreas Forø Tollefsen
Дата:
Сообщение: Calculate the ratio
Следующее
От: "David Johnston"
Дата:
Сообщение: Re: Calculate the ratio