Re: Recursive join - blind alley?

"Roger" <lesperancer_at_natpro.com> wrote in message news:8c7a509f.0401060445.21d14088_at_posting.google.com...
> interesting articles...
> but I don't understand the math in the first article
> he says
>
> function child_numer
> ( num integer, den integer, child integer )
> RETURN integer IS
> BEGIN
> RETURN num*power(2, child)+3-power(2, child);
> END;
>
> function child_denom
> ( num integer, den integer, child integer )
> RETURN integer IS
> BEGIN
> RETURN den*power(2, child);
> END;
>
> select child_numer(3,2,3) || '/' ||
> child_denom(3,2,3) from dual
>
> 19/16
>
> but I get, using an evaluation order [power] -> [*/] -> [+-]
> num*power(2, child)+3-power(2, child)
> 3*power(2,3)+3-power(2,3)
> 3*9+3-9
> 27+3-9
> 21
>
> and
> den*power(2, child)
> 2*power(2, 3)
> 2*9
> 18

power(2,3) = 8 != 9

Do different vendors implement power differently??? Received on Tue Jan 06 2004 - 18:39:30 CET