Horton

Re: Performance issue in foreign-key-aware join estimation

David Rowley <david.rowley@2ndquadrant.com>

View thread View on postgr.es
From: David Rowley <david.rowley@2ndquadrant.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Tomas Vondra <tomas.vondra@2ndquadrant.com>
Date: 2019-02-21T02:05:14Z
Lists: pgsql-hackers 
On Thu, 21 Feb 2019 at 15:00, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Pushed that one.  I'm interested by the "POC" patch, but I agree
> that it'd take some research to show that it isn't a net negative
> for simple queries.  It sounds like you're not really interested
> in pursuing that right now?

Thanks for pushing it.

I'm still interested in the POC patch. I just knew it wasn't something
for the back branches and thought something that was would be more
important... Things having gone quiet here wasn't a good source of
inspiration to do any further work on it. It's good to hear you're
interested.

> Anyway, I rebased the POC patch up to HEAD, just in case anyone
> still wants to play with it.

Cool. Thanks.

-- 
 David Rowley                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services

Commits

  1. Adjust overly strict Assert

  2. Speed up finding EquivalenceClasses for a given set of rels

  3. Speed up match_eclasses_to_foreign_key_col() when there are many ECs.