Re: Why we don't want hints Was: Slow count(*) again...
Kevin Grittner <kevin.grittner@wicourts.gov>
From: "Kevin Grittner" <Kevin.Grittner@wicourts.gov>
To: <sthomas@peak6.com>
Cc: "Josh Berkus" <josh@agliodbs.com>, "Robert Haas" <robertmhaas@gmail.com>, "pgsql-performance@postgresql.org" <pgsql-performance@postgresql.org>
Date: 2011-02-10T17:21:51Z
Lists: pgsql-hackers, pgsql-performance
Shaun Thomas <sthomas@peak6.com> wrote: > how difficult would it be to add that syntax to the JOIN > statement, for example? Something like this syntax?: JOIN WITH (correlation_factor=0.3) Where 1.0 might mean that for each value on the left there was only one distinct value on the right, and 0.0 would mean that they were entirely independent? (Just as an off-the-cuff example -- I'm not at all sure that this makes sense, let alone is the best thing to specify. I'm trying to get at *syntax* here, not particular knobs.) -Kevin