Re: Counting booleans for two columns

Поиск
Список
Период
Сортировка
От Oliveiros C,
Тема Re: Counting booleans for two columns
Дата
Msg-id 2A2D38B5C3894323B34A530F557CF028@marktestcr.marktest.pt
обсуждение исходный текст
Ответ на Counting booleans for two columns  (Rikard Bosnjakovic <rikard.bosnjakovic@gmail.com>)
Ответы Re: Counting booleans for two columns
Список pgsql-novice
SELECT sum(played::integer), sum(stats_exists::integer)
FROM matches
WHERE origin=1 AND stats_exists AND NOT training AND match_date > '2009-08-01';
 
Your approach is elegant, Thom.
 
But if it is to do it that way then I guess
you should drop the "AND stats_exists" part of the query because
it will filter out every line with stats_exists == f, and those (occasionally) played== t won't get summed up  by the SUM() function,
ain't I right ?
 
Best,
Oliveiros
----- Original Message -----
Sent: Friday, November 20, 2009 2:30 PM
Subject: Re: [NOVICE] Counting booleans for two columns

2009/11/20 Rikard Bosnjakovic <rikard.bosnjakovic@gmail.com>
I have a table with values similiar to this (I have reduced the number
of rows from the actual table):

 played | stats_exists
--------+--------------
 t      | t
 t      | f
 t      | t
 t      | t
 f      | t
 t      | t
 t      | f

What I want to do is to count the number of "t" in each column and
return the values (in two separate columns). The only thing I've
managed to do is doing a UNION, but this gives me the (correct)
results in one column only, I want the results in two (I need to
distinguish between the numbers). I did like this:

 SELECT count(played) AS played
 FROM matches
 WHERE origin=1 AND played AND NOT training AND match_date > '2009-08-01'
UNION
 SELECT count(stats_exists) AS stats
 FROM matches
 WHERE origin=1 AND stats_exists AND NOT training AND match_date > '2009-08-01';

with this result:

 played
--------
    12         <-- stats
    13         <-- played
(2 rows)

How can I rewrite the SELECT so I get two values in separate columns
instead of two rows?


Try:

SELECT sum(played::integer), sum(stats_exists::integer)
FROM matches
WHERE origin=1 AND stats_exists AND NOT training AND match_date > '2009-08-01';

If you're using an old version of PostgreSQL, you might have to use:

SELECT sum(case played when true then 1 else 0 end), sum(case stats_exists when true then 1 else 0 end)
FROM matches
WHERE origin=1 AND stats_exists AND NOT training AND match_date > '2009-08-01';

Regards

Thom

В списке pgsql-novice по дате отправления:

Предыдущее
От: "Oliveiros C,"
Дата:
Сообщение: Re: Counting booleans for two columns
Следующее
От: Thom Brown
Дата:
Сообщение: Re: Counting booleans for two columns