Re: [PATCHES] WITH RECURSIVE updated to CVS TIP

On Wed, Jul 16, 2008 at 01:57:04PM +0900, Tatsuo Ishii wrote:
> > > No idea. What do you think if we allow only one query name at the
> > > moment.
> >
> > I'm not sure I understand what that has to do with sorting.
> >
> > Please find attached a place where I've found some problems sorting by
> > tree by array as Asaba-san suggested.
>
> Humm. your problem seems to do nothing with the problem I refer to.

Sorry about that. Is my problem reproducible? Is there maybe some
way to include regression tests around it?

> What I have in my mind is something like:
>
> WITH RECURSIVE foo(a, b) AS
> (SELECT ... UNION SELECT...),
>
> bar(c, d) AS
> (SELECT ... FROM foo WHERE ...UNION...)
> )
> SELECT * FROM foo;
>
> In this there are two query names (foo, bar) and we need to detect the
> dependency that bar relies on foo before processing the query.

I think mutually recursive queries may have been dropped from
SQL:2008.

> However, as I said earlier, this kind of use case would be rare in
> the real world, and I'd like to limit ourselves to having only one
> query name at the moment.
>
> Also I suggest to concentrate on reviewing the WITH RECURSIVE
> implementation itself now, rather than discussing how to use git
> repository or how to write an interesting WITH RECURSIVE
> applications.
>
> Don't get me wrong. I believe git is a great tool. But we have
> limited time and need to think about the priority.

Fair enough :)

Cheers,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter
Skype: davidfetter XMPP: david(dot)fetter(at)gmail(dot)com

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