"Hiroshi Inoue" <Inoue@tpf.co.jp> writes:
>> One way to put a thumb on the scales is to reduce the value of the SET
>> variable random_page_cost. The default value is 4.0, which seems to
>> correspond more or less to reality, but reducing it to 3 or so would
>> shift the planner pretty nicely in the direction of indexscans.
> Or how about changing current fudge factor ?
> For example,from 0.5 to 0.2 which is the fudge factor of attdisbursion
> calculation.
Yes, that's another way --- and probably more defensible than changing
random_page_cost, now that I think about it. Unfortunately it's a
hardwired constant and so not as easily experimented with :-(.
regards, tom lane