On Tue, Dec 12, 2017 at 10:46 PM, Thomas Munro <
thomas(dot)munro(at)enterprisedb(dot)com> wrote:
> Hi hackers,
>
> The start-up cost of bounded (top-N) sorts is sensitive at the small
> end of N, and the
> comparison_cost * tuples * LOG2(2.0 * output_tuples) curve doesn't
> seem to correspond to reality.
Do we want the cost-estimate to be accurate for the worst case (which is
not terribly unlikely to happen, input order is opposite of desired output
order), or for the average case?
Cheers,
Jeff