Re: [HACKERS] Hints proposal

From: Andrew Sullivan <ajs(at)crankycanuck(dot)ca>
To: pgsql-hackers(at)postgresql(dot)org, pgsql-performance(at)postgresql(dot)org
Subject: Re: [HACKERS] Hints proposal
Date: 2006-10-12 19:03:47
Message-ID: 20061012190347.GD29203@phlogiston.dyndns.org
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers pgsql-performance

On Thu, Oct 12, 2006 at 02:21:55PM -0400, Merlin Moncure wrote:
> third way: to solve the problem of data (especially constants) not
> being available to the planner at the time the plan was generated.
> this happens most often with prepared statements and sql udfs. note
> that changes to the plan generation mechanism (i think proposed by
> peter e a few weeks back) might also solve this.

You're right about this, but you also deliver the reason why we don't
need hints for that: the plan generation mechanism is a better
solution to that problem. It's this latter thing that I keep coming
back to. As a user of PostgreSQL, the thing that I really like about
it is its pragmatic emphasis on correctness. In my experience, it's
a system that feels very UNIX-y: there's a willingness to accept
"80/20" answers to a problem in the event you at least have a way to
get the last 20, but the developers are opposed to anything that
seems really kludgey.

In the case you're talking about, it seems to me that addressing the
problems where they come from is a better solution that trying to
find some way to work around them. And most of the use-cases I hear
for a statement-level hints system fall into this latter category.

A
--
Andrew Sullivan | ajs(at)crankycanuck(dot)ca
Unfortunately reformatting the Internet is a little more painful
than reformatting your hard drive when it gets out of whack.
--Scott Morris

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Jim C. Nasby 2006-10-12 19:06:20 Re: SQL functions, INSERT/UPDATE/DELETE RETURNING, and triggers
Previous Message Tom Lane 2006-10-12 19:03:43 Re: SQL functions, INSERT/UPDATE/DELETE RETURNING, and triggers

Browse pgsql-performance by date

  From Date Subject
Next Message Jeff Davis 2006-10-12 19:07:11 Re: Hints proposal
Previous Message Tom Lane 2006-10-12 18:25:09 Re: Scrub one large table against another