Re: Optimisation deficiency: currval('seq')-->seq scan, constant-->index scan

Tiago Antão <tra@fct.unl.pt> writes:
>   One thing it might be interesting (please tell me if you think
> otherwise) would be to improve pg with better statistical information, by
> using, for example, histograms.

Yes, that's been on the todo list for a while.

> There is a good article regarding this:
> http://www.db2mag.com/summer00/programmer.shtml

Interesting article.  We do most of what she talks about, but we don't
have anything like the ClusterRatio statistic.  We need it --- that was
just being discussed a few days ago in another thread.  Do you have any
reference on exactly how DB2 defines that stat?
        regards, tom lane