Re: Query 4-5 times slower after ANALYZE

In response to "Philippe Lang" <philippe(dot)lang(at)attiksystem(dot)ch>:
>
> I'm using Postgresql 8.3.6 under Freebsd 7.1.
>
> After a fresh restore of a customer dump (running version 8.2.7 at the
> moment), a rather big query executes in about 30 seconds. As soon as I
> run ANALYZE, it is instantly 4-5 times slower. I could check that
> multiples times.
>
> Here is the EXPLAIN ANALYZE before the ANALYZE:
> http://www.attiksystem.ch/postgresql/query_slower_after_analyze/before.txt
>
> And here the the EXPLAIN ANALYZE after the ANALYZE:
> http://www.attiksystem.ch/postgresql/query_slower_after_analyze/after.txt
>
> Any idea what could be turned on/off in order not to have this slowdown
> after the ANALYZE?

I opened one of those links figuring I'd take a few minutes to see if I could
muster up some advice ... and just started laughing ... definitely not the
type of query that one can even understand in just a few minutes!

Anyway, the real reason I posted -- I doubt if anyone will be able to make
sense of a query plan that complex without the actual query, so you'll
probably want to post it as well.

--
Bill Moran
http://www.potentialtech.com
http://people.collaborativefusion.com/~wmoran/