Postgresql：选择其他字段的唯一对顺序

Question

我想选择最新的（order by id desc）唯一对date_start, date_finish

CREATE TABLE some (
    id SERIAL, 
    date_start TIMESTAMP,
    date_finish TIMESTAMP
);

Answer 1

怎么样：

select date_start, date_finish
from some
group by date_start, date_finish
order by max(id) desc