Re: [PATCHES] WITH RECUSIVE patches 0717

On Fri, Jul 18, 2008 at 07:56:09AM -0700, David Fetter wrote:
> On Fri, Jul 18, 2008 at 10:41:20AM +0900, Tatsuo Ishii wrote:
> > > > Here is the lastest WITH RECURSIVE patches against CVS HEAD created by
> > > > Yoshiyuki Asaba and minor corrections by Tatsuo Ishii.
> > >
> > > I tried this patch vs. CVS HEAD used my usual configure option with
> > > only --with-prefix set, then tried to make, and got:
> > >
> > > make[3]: *** No rule to make target `parse_cte.o', needed by `objfiles.txt'. Stop.
> > > make[3]: Leaving directory `/home/shackle/pgsql/src/backend/parser'
> > > make[2]: *** [parser-recursive] Error 2
> > > make[2]: Leaving directory `/home/shackle/pgsql/src/backend'
> > > make[1]: *** [all] Error 2
> > > make[1]: Leaving directory `/home/shackle/pgsql/src'
> > > make: *** [all] Error 2
> > >
> > > Is there something missing?
> >
> > Oops. I forgot to include patches against newly added files. Please
> > try included patches.
>
> This now compiles.
>
> I have a test case that hangs and smashes.
>
> WITH t(i) AS (
> SELECT * FROM generate_series(1,5)
> )
> SELECT
> t1.i,
> 2*t2.i
> FROM
> t AS t1
> JOIN
> t AS t2 USING(i);
>
> server closed the connection unexpectedly
> This probably means the server terminated abnormally
> before or while processing the request.
> The connection to the server was lost. Attempting reset: Failed.
>
> An equivalent query without RECURSIVE breaks in a different, in some
> sense even more severe, way, as in it just hands out a wrong result
> set:

D'oh! That's what I get for sending this before waking up. It works
just fine.

> While this case is trivial, others are not. For example, if someone
> wishes to do a k-deep summary on a parts explosion n levels deep,
> n>k, one way to do this would be to JOIN the k-deep part of the path
> enumeration to the parts greater than k deep.
>
> What would need to be fixed in order to make the above things work?

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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