Another question:
How are you benchmarking your queries? Are you running them from within
psql? Do you plan to run these queries from within an application?
psql introduces some overhead because it has to scan the result set to
determine the widths of the columns for formatting purposes. Try
returning a result set inside the libpq library if you know C and
compare the times. Of course, if you are already using libpq, this
moot. If you do know libpq, try setting up a loop that fetches the data
in 10k block in a loop...I will wager that you can get this to run in
under two minutes (Q4).
Merlin