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Message-ID: <36e682920804270906i7b5c5ab9v4e06688df85f810@mail.gmail.com>
Date: Sun, 27 Apr 2008 12:06:41 -0400
From: "Jonah H. Harris" <jonah.harris@gmail.com>
To: "Jean-David Beyer" <jeandavid8@verizon.net>
Subject: Re: Curious about wide tables.
Cc: pgsql-sql@postgresql.org
In-Reply-To: <48147917.8000108@verizon.net>
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References: <48147917.8000108@verizon.net>

On Sun, Apr 27, 2008 at 9:01 AM, Jean-David Beyer
<jeandavid8@verizon.net> wrote:
> In another thread, the O.P. had a question about a large table with over 100
>  columns. Is this usual? Whenever I make a database, which is not often, it
>  ends up with tables that rarely have over to columns, and usually less than
>  that. When normalized, my tables rarely get very wide.

Yes, even in several well-normalized schemas I've seen tables with
over 250 columns.

>  Without criticising the O.P., since I know nothing about his application, I
>  am curious how it comes about that such a wide table is justified.

The few applications I've seen with large tables were an insurance
system, an manufacturing system, and a sensor-recording system (which
was more optimal to store as an attribute-per-instance-of-time than a
separate tuple containing the time, sensor, and value).

-- 
Jonah H. Harris, Sr. Software Architect | phone: 732.331.1324
EnterpriseDB Corporation | fax: 732.331.1301
499 Thornall Street, 2nd Floor | jonah.harris@enterprisedb.com
Edison, NJ 08837 | http://www.enterprisedb.com/