Re: Is this JOIN good ?

klabu wrote:
> "DA Morgan"
> > Based upon what you posted I would say that it is impossible to tell.
> > Is a.fk the child of c.pk? I don't know.
> > Is b.fk the child of c.pk? I don't know.
> > And even if they are ... it is impossible to know if these single
> > relationships are sufficient to avoid a Cartesian product.
> > --
>
> thanks
> Yes, assuming they are of 100% referential integrity there, 100% "Children
> <==> Parent" relationship
> So given this it is still
> "impossible to know if these single relationships are sufficient to avoid a
> Cartesian product." ?
>
> What additional info do you need to know to say "JOIN is complete" ?
>
> thanks
> 10gR2

YES, It is complete. It is not Cartesian. You will get rows that exists in A, B, and C.
Oracle will join A and C and then selected rows with B or

           will join B and C and then result with A.

Thanks,
Aleks Received on Tue Oct 17 2006 - 12:15:31 CDT