Seleccionar "el resto" y sumarlo -¿Como? -

[Jose_minglein2]

Código:

 select country, count(provider_id)as total
from provider group by country order by total DESC Limit 5 
UNION
Select 'otros' as country, count(provider_id) as total from provider where provider_id not in (select provider_id
from provider group by country order by total DESC Limit 5 )

Espero que te sirva