Re: Primary and Foreign Key constraints

"Lars Steinmetz" <no_spam_lsteinmetz_at_jakrause.com> wrote in message news:1031553251.430831_at_news.thyssen.com...
> Hello NG,
>
> I have an Oracle Database witch work's with an old client software
> programmed i C++. The client software installed all tables, indexes,
> sequences ect. by itself. Looking into the Oracle-DB, I recognized that no
> primay and no foreign key constraints are implemented. That means that all
> referneces are only known by the client program. Not very stylish...
> Will adding primary key and foreign key constraints to the databases
> increase the performance?
>
> Thanx for any response.

It depends!

If the keys are already indexed then I'd suggest the performance benefits you'd get would be slight. It seems quite likely to me that you will have unindexed FK's though.

The other thing to consider is wether yu would be invalidating the vendor's support by doing this sort of thing. My guess would be that you are. What happens if the key you identify as a foreign key turns out not in fact to be a foreign key at all.

--
Niall Litchfield
Oracle DBA
Audit Commission UK
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