Re: Grouping by date range
| От | Alexander Litvinov |
|---|---|
| Тема | Re: Grouping by date range |
| Дата | |
| Msg-id | 200308191456.48517.lan@ac-sw.com обсуждение исходный текст |
| Ответ на | Grouping by date range (Mat <psql-mail@freeuk.com>) |
| Ответы |
Re: Grouping by date range
Re: Grouping by date range |
| Список | pgsql-general |
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I home your date field have date type. If it is try this:
select date_part('year', date), count(*) from your_table group by
date_part('year', date) order by date_part('year', date);
for month add grouping by date_part('month', date)
if you need to handle large number of rows try to add columns with year and
month, write triggers for filling this columns, make indexes and things
should be fast.
> date | data
> ---------------
> 01/01/01| 123
> 01/01/01| abc
> 02/01/01| def
> 03/03/01| hij
>
> I can see how to group by day - but how do i go about decreasing the
> precision down to months/years.
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