Re: Queries taking ages in PG 8.1, have been much faster in PG<=8.0

"Markus Wollny" <Markus.Wollny@computec.de> writes:
> My current problem is that rewriting hundreds of queries, some of them
> quite a bit more complex than this one, but all of them using the same
> general scheme, would take quite a lot of time - and I'm expected to
> hand over the survey results ASAP. So I will obviously have to do a
> rewrite if there's just no other way, but I wondered if there might be
> some other option that would allow me to point the planner in the right
> direction so it would behave the same as in the previous versions,
> namely 8.0?

It looks like "set enable_nestloop = 0" might be a workable hack for
the immediate need.  Once you're not under deadline, I'd like to
investigate more closely to find out why 8.1 does worse than 8.0 here.

            regards, tom lane