> Afterthought: It would be nice if the database was smart enough to
> analyze a table of its own accord when a sequential scan returns more
> than, say, 20 times what it was supposed to.
I've wondered on several occasions if there is any good reason for PG not
to automatically perform an analyze concurrently with a seq scan as it's
happening. That way, no extra disk IO is needed and the stats could say
up-to-date for almost free.
Any hackers around who can say why this might be a bad idea, or is it one
of those things that just needs a volunteer? (I'm not; at least not now.)