> with QRY as (select C1.country, C1.state, sum(C1.population)
> from places C1
> group by 1, 2
> order by 3 DESC
> limit 10)
>
> select * from QRY
> union
> select 'others' as "country", '' as "state", sum(population)
> from places
> where not exists (select 1 from QRY where country = QRY.country and state
> = QRY.state)
>
(not tested)
with QRY as ( SELECT country, state, sum(population) as st_pop FROM places GROUP BY country, state )
, u1 AS ( SELECT country, state, st_pop FROM QRY ORDER BY st_pop DESC LIMIT 10 )
, u2 AS ( SELECT 'other' AS country, '' AS state, sum(st_pop) FROM QRY WHERE NOT EXISTS (
SELECT 1 FROM u1 WHERE (QRY.country, QRY.state) = (u1.country, u1,state)
