Re: Avoiding bad prepared-statement plans.

Robert Haas <robertmhaas@gmail.com>

From: Robert Haas <robertmhaas@gmail.com>

To: Tom Lane <tgl@sss.pgh.pa.us>

Cc: Mark Mielke <mark@mark.mielke.cc>, Jeroen Vermeulen <jtv@xs4all.nl>, Alex Hunsaker <badalex@gmail.com>, Greg Stark <gsstark@mit.edu>, Bart Samwel <bart@samwel.tk>, Pavel Stehule <pavel.stehule@gmail.com>, pgsql-hackers@postgresql.org

Date: 2010-02-28T01:01:43Z

Lists: pgsql-hackers

On Fri, Feb 26, 2010 at 7:03 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> Basically, what I really want here is some kind of keyword or other
>> syntax that I can stick into a PL/pgsql query that requests a replan
>> on every execution.
>
> Wouldn't it be better if it just did the right thing automatically?
>
> The sort of heuristic I'm envisioning would essentially do "replan every
> time" for some number of executions, and give up only if it noticed that
> it wasn't getting anything better than the generic plan.  So you'd have
> a fixed maximum overhead per session when the custom plan was useless,
> and the Right Thing when it wasn't.

Which is likely useless for my use case.

...Robert