Re: How to query for Interval

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От A. Kretschmer
Тема Re: How to query for Interval
Дата
Msg-id 20060412053003.GA1271@webserv.wug-glas.de
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Ответ на How to query for Interval  ("Vishal Kashyap " <vishalonlist@gmail.com>)
Ответы Re: How to query for Interval
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am  12.04.2006, um  2:23:12 +0530 mailte Vishal Kashyap  folgendes:
> Hi,
>
>
> I have a table with time stamps in it . These timestamp represent a event count.
> I just wanted to know how could I query such that I get a count of
> event per hour.
>
> Table structure is
>
> my_table(id serial, time_event timestamp,event varchar(200));
>
> I want to do something like
> select count(id) from  my_table where time_event in (every 1 hour);

*untested*

select x, count(b.*)
    from generate_series(0,23) x,
        my_table y
    where date_trunc('hour', y.time_event) '2006/04/12'::date + (x||'hour')::interval
    group by x
    order by x;

The result should be a table for every hour for the given date.


HTH, Andreas
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