Re: counts of groupings by date year-month
От | Andreas Kretschmer |
---|---|
Тема | Re: counts of groupings by date year-month |
Дата | |
Msg-id | 20090227215215.GA12288@tux обсуждение исходный текст |
Ответ на | counts of groupings by date year-month (Carol Cheung <cacheung@consumercontact.com>) |
Список | pgsql-sql |
Carol Cheung <cacheung@consumercontact.com> wrote: > Hi, > I have a table called temp > > access_date | active | status > -------------+--------+-------- > 2009-02-01 | t | 15 > 2009-02-01 | f | 16 > 2009-02-02 | f | 17 > 2009-02-01 | t | 17 > 2009-02-02 | f | 21 > 2009-01-01 | t | 20 > 2009-01-01 | t | 21 > 2009-01-01 | f | 21 > > > What I want is to be able to get counts of active by year-month. So the > output would be like: > > year_month | count > ------------+------- > 200901 | 3 > 200902 | 5 > > I tried something like > SELECT to_char(access_date, 'YYYYMM') as year_month, count(year_month) > FROM temp GROUP BY year_month ORDER BY year_month; > > but I'm unable to execute this query because the column "year_month" > doesn't exist in temp table. > > Is it possible to get counts by year_month? change count(year_month) to count(1), untested. Andreas -- Really, I'm not out to destroy Microsoft. That will just be a completely unintentional side effect. (Linus Torvalds) "If I was god, I would recompile penguin with --enable-fly." (unknown) Kaufbach, Saxony, Germany, Europe. N 51.05082°, E 13.56889°
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