Re: [HACKERS] WITH RECURSIVE updated to CVS TIP

hello david,

i did some quick testing with this wonderful patch.
it seems there are some flaws in there still:

test=# explain select count(*)
test-#         from ( WITH RECURSIVE t(n) AS ( SELECT 1 UNION ALL  
SELECT DISTINCT n+1 FROM t )
test(#                 SELECT * FROM t WHERE n < 5000000000) as t
test-#         WHERE n < 100;
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.
!> \q

this one will kill the planner :(
removing the (totally stupid) distinct avoids the core dump.


i found one more issue;

-- broken: wrong result
test=# select count(*) from ( WITH RECURSIVE t(n) AS (
         SELECT 1 UNION ALL SELECT n + 1 FROM t)
         SELECT * FROM t WHERE n < 5000000000) as t WHERE n < (
                 select count(*) from ( WITH RECURSIVE t(n) AS (
                         SELECT 1 UNION ALL SELECT n + 1 FROM t )
         SELECT * FROM t WHERE n < 5000000000) as t WHERE n < 100) ;
  count
-------
      1
(1 row)

if i am not totally wrong, this should give us a different result.

i am looking forward to see this patch in core :).
it is simply wonderful ...

	many thanks,

		hans






On Jul 3, 2008, at 1:11 AM, David Fetter wrote:

> Folks,
>
> Please find patch enclosed, including some documentation.
>
> Can we see about getting this in this commitfest?
>
> Cheers,
> David.
> -- 
> David Fetter <[email protected]> http://fetter.org/
> Phone: +1 415 235 3778  AIM: dfetter666  Yahoo!: dfetter
> Skype: davidfetter      XMPP: [email protected]
>
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