"Michal J. Kubski" <michal.kubski@cdt.pl> writes:
> [ function that creates a bunch of temporary tables and immediately
> joins them ]
It'd probably be a good idea to insert an ANALYZE on the temp tables
after you fill them. The way you've got this set up, there is no chance
of auto-analyze correcting that oversight for you, so the planner will
be planning the join "blind" without any stats. Good results would only
come by pure luck.
regards, tom lane