Re: [PATCHES] [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.

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