sqlite subquery syntax error

I have a syntax error in this subquery that I cannot seem to figure out w开发者_如何学JAVAhy it won't work. All the parens are matched

select min(max_s) 
from 
(select max(salary) from instructor group by dept_name) 
as s(max_s);

Error: near "(": syntax error

Use:

SELECT MIN(x.max_s) 
  FROM (SELECT MAX(i.salary) AS max_s 
          FROM INSTRUCTOR i
      GROUP BY i.dept_name) x

The problem is in the AS s(max_s) table alias, which doesn't look quite right. You should alias the column name inside the subquery, for example:

select min(s.max_s) 
from 
(select max(salary) as max_s from instructor group by dept_name) 
as s

Don't put parens after a table alias.