A couple of links:
http://www.dbazine.com/ofinterest/oi-articles/celko24
http://www.dbmsmag.com/9603d06.html
On Jun 2, 2005, at 2:33 AM, Joachim Zobel wrote:
> Hi.
>
> I am looking for a way to write a SELECT that finds connectivity
> components of a graph or at least for one that given two nodes
> determines if there is a path between them. It seems that this is not
> possible, no matter what graph representation I choose. Which
> constructs
> from set theory are missing in SQL? Set of all subsets is one I am
> missing, or can it be done somehow?
>
> Is anybody else thinking about the limits of SQL? As often I am
> probably
> not the first to ask these questions. Any pointers?
>
> Sincerely,
> Joachim
>
>
>
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