Re: Problems with substring

Thanx to u and Stuart

i was really busting my head on this one.

-----Original Message-----
From: Josh Berkus [mailto:josh@agliodbs.com]
Sent: Tuesday, September 10, 2002 5:34 PM
To: Duncan Adams (DNS); pgsql-novice@postgresql.org
Subject: Re: [NOVICE] Problems with substring


Ducan,

> I am using postgres 7.1.3
> on redhat 7.2.

First, please consider upgrading.   7.2.1 has a lot of enhancements
over 7.1.3, and we're testing 7.3.0 now!

> drop view wm_ups_count;
> create view wm_ups_count as
> select
>  substring(phase from 1 for 1) as ups,
>  sys_key,
>  count(substring(phase from 1 for 1)) as phas_count
> from
>  power
> where
>  sys_key = 10
> group by
>  sys_key,
>  phase;
^^^^^^^^^^^^^

This is your problem.  It should be:
GROUP BY sys_key, substring(phase from 1 for 1);

If you GROUP BY something other than the columns you are displaying,
you will often see "duplicate" rows.

-Josh Berkus

______AGLIO DATABASE SOLUTIONS___________________________

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