Martin Below <machtin(dot)below(at)googlemail(dot)com> writes:
> test=# select count(*) total, count(distinct client_id) ids,
> count(distinct expires_on) dates from ps;
> total | ids | dates
> --------+--------+--------
> 213645 | 123366 | 213549
That says the expires_on column is practically unique, which makes me
think the planner is indeed making the right choice.
regards, tom lane