Am Donnerstag, den 02.06.2005, 12:46 -0700 schrieb Ben:
> You mean, you want to be able to say something like:
>
> select isConnected(a,b)
>
> and get back a true/false, or maybe the path?
>
> That seems quite doable in SQL, assuming you either store those results
> and simply use sql to retrieve them, or use a stored proc to compute the
> result each time.
These are both things I want to avoid. I am not trying to solve a real
world problem, I want to understand the limits of SQL. And it seems that
a plain SELECT that tells me if a path exists is not possible. However I
just read nested sets (thx for the link, Sean). Maybe a tricky
representation does it.
Sincerely,
Joachim