Talk About Network

Google


Register and Login
Nick
Password
Register create new account Sign up is FREE and you can post replies, new topics, bookmark posts and more!
Recover lost password


Data Bases > Pgsql Patches > Re: [HACKERS] W...
Latest [ Topics | Posts ] Archive Post A New Topic Post a Reply
<< Topic < Post Post 2 of 2 Topic 3864 of 4088
Post > Topic >>

Re: [HACKERS] WITH RECURSIVE updated to CVS TIP

by david@[EMAIL PROTECTED] (David Fetter) Jul 5, 2008 at 03:15 PM

On Sat, Jul 05, 2008 at 10:43:57AM +0200, Hans-Juergen Schoenig wrote:
> 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.

Any idea why this might be happening?

> 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.

What result should it give, and what do you think is going wrong here?

> i am looking forward to see this patch in core :).

So am I :)

> it is simply wonderful ...
>
> 	many thanks,

Thanks go to the kind people who actually wrote the thing.  I've just
been using git to keep the bit-rot off it :)

Cheers,
David.
-- 
David Fetter <david@[EMAIL PROTECTED]
> http://fetter.org/
Phone: +1 415 235 3778  AIM: dfetter666  Yahoo!: dfetter
Skype: davidfetter      XMPP: david.fetter@[EMAIL PROTECTED]
 to vote!
Consider donating to Postgres: http://www.postgresql.org/about/donate

-- 
Sent via pgsql-patches mailing list (pgsql-patches@[EMAIL PROTECTED]
)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-patches
 




 2 Posts in Topic:
Re: [HACKERS] WITH RECURSIVE updated to CVS TIP
postgres@[EMAIL PROTECTED  2008-07-05 10:43:57 
Re: [HACKERS] WITH RECURSIVE updated to CVS TIP
david@[EMAIL PROTECTED]   2008-07-05 15:15:00 

Post A Reply:
  Go here to Signup

AddThis Feed Button


About - Advertising - Contact - Frequently Asked Questions - Privacy Policy - Terms of Use - Signup

Contact
tan12V112 Sun Oct 12 9:37:26 CDT 2008.