Re: CONNECT BY PRIOR

On T, 2005-11-15 at 09:53 +0100, Martijn van Oosterhout wrote:
> On Tue, Nov 15, 2005 at 01:38:31AM -0500, Jonah H. Harris wrote:
> > Hey Simon,
> > I'm doing some research into recursive query planning in terms of theory
> > as-well-as actual implementation in other RDBMS. Let me get back to you when
> > I have some more definitive info.
>
> My first reaction would be to have a sort of Repeat node, with two
> subnodes, the Tail and the Loop. The procedure would be to extract a
> tuple from the Tail (optionally returning it). Then put that tuple
> as the input to the Loop and start pulling tuples out of that.

Will this work for both DEPTH FIRST and BREADTH FIRST recursion ?

> Problem is, those new tuples may have to be sent through the loop again
> so you have a buffering problem. But it seems a fairly generic way of
> dealing with it.
>
> Ofcourse, once you've done that, you might be getting very close to a
> Turing complete executor, no? :)
>
> Have a nice day,

--
Hannu Krosing <hannu(at)skype(dot)net>