Re: How many FKs is too many ?

From: DA Morgan <damorgan_at_x.washington.edu>
Date: Thu, 21 Oct 2004 22:51:12 -0700
Message-ID: <1098424219.831695@yasure>

Joel Garry wrote:

> krislioe_at_gmail.com (xtanto) wrote in message news:<e1c9bd55.0410210337.2957db19_at_posting.google.com>...
>

>>Hi Oracle gurus,
>>
>>I have two tables, one with 100.000 rows and the other with about 4
>>million rows. Each table has about 55 columns, with 15 of them refer
>>to a reference Table.
>>
>>If I put FK constraint on these 15 columns (mean I have 15 FKs).
>>Is this too many ? will this cause poor performance ? 
>>Is there any best practices for this ?
>>
>>Thank you for your help,
>>xtanto

>
>
> I have a table with 4M rows, a primary key that has 25 columns on it,
> with 4 other indices. It has very poor performance. But that's what
> happens when you take a poor packaged design and make it worse with
> customizations for business rules.
>
> So I can't change the design or get rid of the customizations. But I
> can make it work (which appears to be more than the people who
> originally did the customizations can say). It's a living. Not
> something I'd recommend. I'd recommend what everyone else is saying,
> fix the design. But it really depends on what you are doing with the
> table. I'm certainly not doing OLTP on it! Meaning, define
> performance. If a report runs overnight, so what? If a customer is
> lost because "the computer is down," big problem!
>
> jg
> --
> @home.com is bogus.
> What's in your database? http://www.securityfocus.com/news/9758

Did you consider an IOT with OVERFLOW?

-- 
Daniel A. Morgan
University of Washington
damorgan_at_x.washington.edu
(replace 'x' with 'u' to respond)

Received on Fri Oct 22 2004 - 00:51:12 CDT