Steinar,
> sort_mem is already 16384, which I thought would be plenty -- I tried
> increasing it to 65536 which made exactly zero difference. :-)
Well, then the next step is increasing the statistical sampling on the 3 join
columns in that table. Try setting statistics to 500 for each of the 3
cols, analyze, and see if that makes a difference.
--
-Josh Berkus
Aglio Database Solutions
San Francisco