date       val   count
2017-01-25 ua5    50
2017-01-25 ua6    49
2017-02-25 ua8    35
2017-02-25 ua3    20
2017-01-25 ua1     2
2017-01-25 ua2     2
2017-02-25 ua9     1
2017-02-25 ua7     1
2017-01-25 ua4     1

date       val   count
2017-01-25 ua5    50
2017-01-25 ua6    49
2017-02-25 ua8    35
2017-02-25 ua3    20
2017-01-25 other   5
2017-02-25 other   2

select date, (case when count <= 10 then 'other' else val end) as val, sum(count)
from table t
group by date, (case when count <= 10 then 'other' else val end);