Re: Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?

Tom Lane wrote:
> Given that it estimated 1 row out of "words" (quite correctly) and 12264
> rows out of each scan on article_words, you'd think that the join size
> estimate would be 12264, which would be off by "only" a factor of 3 from
> the true result.  Instead it's 23, off by a factor of 200 :-(.
>
Has anyone every proposed a "learning" query planner?  One that
eventually clues in to estimate mismatches like this?