Re: How many FKs is too many ?

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

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