Csaba Nagy <nagy(at)ecircle-ag(dot)com> writes:
> OK, maybe that's the point... the "cost bust" given to the sequential
> scan by enable_seqscan=off is not enough in this case to exceed the cost
> of the index scan ?
Looks that way to me. You could try setting enable_sort off as well,
which will penalize the seqscan+sort plan another 100million cost units.
And maybe try reducing random_page_cost to make the indexscan look
cheaper. However, if there's a 100million delta between the two plans,
I suspect you really really don't want the indexscan anyway ;-)
regards, tom lane