"Joshua Marsh" <icub3d@gmail.com> writes:
>> Are the tables perhaps nearly in order by the dsiacctno fields?
> My assumption would be they are in exact order. The text file I used
> in the COPY statement had them in order, so if COPY preserves that in
> the database, then it is in order.
Ah. So the question is why the planner isn't noticing that. What do
you see in the pg_stats view for the two dsiacctno fields --- the
correlation field in particular?
> The system has 8GB of ram and work_mem is set to 256MB.
Seems reasonable enough. BTW, I don't think you've mentioned exactly
which PG version you're using?
regards, tom lane