Search Postgresql Archives

Re: setting for maximum acceptable plan cost?

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On Fri, 02 Nov 2007 13:49:27 -0700
"Jeffrey W. Baker" <jwbaker@xxxxxxx> wrote:

> Nested Loop Left Join  (cost=13920.16..2257575559347.46
> rows=3691992705807 width=128)
> 
> After a call to ANALYZE, the same query gave me:
> 
> Merge Left Join  (cost=16382.02..16853.87 rows=126768 width=59)
> 
> And runs in 5 seconds.  If I had been able to tell pg to reject any
> plan with cost over, say 10E9, that would have saved my server from
> half an hour of nested sequential scans.

I am confused as to why you would want to do that... seems like a
band aid for lack of maintenance.

> 
> Should I just use statement_timeout as a proxy for this?
> 

That would yes but see my point about maintenance above.

Joshua D. Drake



- -- 

      === The PostgreSQL Company: Command Prompt, Inc. ===
Sales/Support: +1.503.667.4564   24x7/Emergency: +1.800.492.2240
PostgreSQL solutions since 1997  http://www.commandprompt.com/
			UNIQUE NOT NULL
Donate to the PostgreSQL Project: http://www.postgresql.org/about/donate
PostgreSQL Replication: http://www.commandprompt.com/products/

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (GNU/Linux)

iD8DBQFHK5peATb/zqfZUUQRAttyAJ9pHjQUuyY7e2cJXtkB2239vOqAxACfX2XW
AHVlhc4g/mzc7uesWpAGls0=
=i6n+
-----END PGP SIGNATURE-----

---------------------------(end of broadcast)---------------------------TIP 1: if posting/reading through Usenet, please send an appropriate       subscribe-nomail command to majordomo@xxxxxxxxxxxxxx so that your       message can get through to the mailing list cleanly

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Postgresql Jobs]     [Postgresql Admin]     [Postgresql Performance]     [Linux Clusters]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Postgresql & PHP]     [Yosemite]
  Powered by Linux