On Thu, 20 Jun 2002 22:50:04 -0400 (EDT)
"Bruce Momjian" <pgman@candle.pha.pa.us> wrote:
> I have thought that some type of feedback from the executor back into
> the optimizer would be a good feature. Not sure how to do it, but your
> idea makes sense. It certainly could update the table statistics after
> a sequential scan.
Search the archives for a thread I started on -hackers called "self-tuning
histograms", which talks about a pretty similar idea. The technique there
applies only to histograms, and builds the histogram based *only* upon
the data provided by the executor.
Tom commented that it's probably a better idea to concentrate on more
elementary techniques, like multi-dimensional histograms, before starting
on ST histograms. I agree, and plan to look at multi-dimensional histograms
when I get some spare time.
Cheers,
Neil
--
Neil Conway <neilconway@rogers.com>
PGP Key ID: DB3C29FC