Re: PK vs Unique index

Correct! You are not comparing an Apple with an Apple here. If you only craete a unique index then if the Index is corrupted or invalid then I believe that an insert will succeed. However it will fail if a constraint exists and the index is corrupted.

Stephen B wrote (on Tue, 15 Jan 2002 13:55:29):

> Hi Phil,
>
> At the risk of stating the obvious, a unique index will allow NULL
> values...I'd only be guessing about performance..I'm just saying that
> you're comparing two different functionalities (one with unique/no nulls and
> one with unique only)..
>
> It seems to me that it's more a question of what you require than a
> performance issue...
>
> I hope this helps,
>
> Steve
>
> "Philip Morrow" <cracker_at_mymorrow.com> wrote in message
> news:kQW08.45721$_p.11054374_at_typhoon.tampabay.rr.com...
> > Is there any performance difference is you use a PK constraint vs just
> > creating a unique index. I know the PK will create the unique index as
> > well, but is there a disadvantage to creating just a index and not a PK
> > constraint
> >
> > Thanks
> > Phil
> >
> >
Received on Tue Jan 15 2002 - 23:36:00 CET