Re: 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 <david(at)fetter(dot)org> http://fetter.org/
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