Seeking help with a query....

Поиск
Список
Период
Сортировка
От Dan Winslow
Тема Seeking help with a query....
Дата
Msg-id gyGea.116460$JE5.71106@news2.central.cox.net
обсуждение исходный текст
Ответы Re: Seeking help with a query....  ("Victor Yegorov" <viy@pirmabanka.lv>)
Список pgsql-sql
Hi folks, seeking help with a query that I thought was simple, but
apparantly isn't, at least for someone with my knowledge level.

Given a table :

create table atable ( code1 char, code2 char, cost    int
);

And the rows

code1    code2    cost
-----------------------------
a            b            2
d            e            4
b            a            6
f            g            1

I need a ( preferably single ) query that will sum the costs for any
matching pairs of codes regardless of order. That is, row 1 and row 3
concern the same pair of unordered codes (a,b), and the result should show
that the (a,b) pair had a summed cost of 8. I am not able to change any of
the environment or preconditions other than the query itself. I have tried
so many approaches that they aren't even worth listing. Any suggestions
would be very much appreciated.





В списке pgsql-sql по дате отправления:

Предыдущее
От: "Dan Winslow"
Дата:
Сообщение: Diffcult query
Следующее
От: "Mario Alberto Soto Cordones"
Дата:
Сообщение: