am Thu, dem 24.05.2007, um 14:49:47 -0400 mailte Edward W. Rouse folgendes:
> I have an audit table that I am trying to get a count of the number of distinct
> entries per day by the external table key field. I can do a
>
> select count(distinct(id)) from audit where timestamp >= '01-may-2007'
>
> and get a total count. What I need is a way to group on each day and get a
> count per day such that the result would be something like
>
> date count
> 01-may-2007 107
> 02-may-2007 215
> 03-may-2007 96
> 04-may-2007 0
>
>
> I would prefer the 0 entries be included but can live without them. Thanks.
You are searching for GROUP BY.
A simple example:
test=*# select * from foo; ts | val
---------------------+-----2007-05-01 08:00:00 | 102007-05-01 08:00:00 | 202007-05-02 10:00:00 | 202007-05-02
11:00:00| 30
(4 rows)
Time: 1.079 ms
test=*# select ts::date, sum(val) from foo group by 1; ts | sum
------------+-----2007-05-02 | 502007-05-01 | 30
(2 rows)
Andreas
--
Andreas Kretschmer
Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header)
GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net
