SQL查询前五条数据及其他所有数据之和

知识管理反馈系统中，分析知识检索的办公室（北京上海天津香港纽约东京....苏州）来源，我需要查询哪些办公室次数较多，排出前5个，并计算出剩余所有部门的查询次数之和。

数据库是mysql。

1 拼出前五个

select sum(count) as total,location from tb_person group by location limit 5;

2.检索其他所有

理论上应该是：

select '其它',sum(count) from tb_person where location not in (select location from tb_person group by location limit 5);

但是sql无法执行，提示：
This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery

子查询中无法使用limit，检索到解决方案是在此再套一层查询，拼出来：

select '其它',sum(count) from tb_person where location not in (select t.location from (select location from tb_person group by location limit 5) as t);

成功得到结果~