Re: Pull up aggregate subquery - Mailing list pgsql-hackers

From Ross J. Reedstrom
Subject Re: Pull up aggregate subquery
Date
Msg-id 20110525172114.GC31648@rice.edu
Whole thread Raw
In response to Re: Pull up aggregate subquery  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
On Mon, May 23, 2011 at 11:08:40PM -0400, Robert Haas wrote:
> 
> I don't really like the idea of adding a GUC for this, unless we
> convince ourselves that nothing else is sensible.  I mean, that leads
> to conversations like this:
> 
> Newbie: My query is slow.
> Hacker: Turn on enable_magic_pixie_dust and it'll get better.
> Newbie: Oh, yeah, that is better.  Why isn't this turned on by default, anyway?
> Hacker: Well, on pathological queries, it makes planning take way too
> long, so we think it's not really safe to enable it by default.
> Newbie: Wait... I thought you just told me to enable it.  It's not safe?
> Hacker: Well, sort of.  I mean, uh... hey, look, an elephant!
> 

ROTFL! This needs to go on the wiki somewhere discussing why HACKERs
rejects tunable knobs as often as happens.

Ross
-- 
Ross Reedstrom, Ph.D.                                 reedstrm@rice.edu
Systems Engineer & Admin, Research Scientist        phone: 713-348-6166
Connexions                  http://cnx.org            fax: 713-348-3665
Rice University MS-375, Houston, TX 77005
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