找出所有员工当前薪水salary情况

CREATE TABLE `salaries` (
`emp_no` int(11) NOT NULL,
`salary` int(11) NOT NULL,
`from_date` date NOT NULL,
`to_date` date NOT NULL,
PRIMARY KEY ( `emp_no` , `from_date` ));

select distinct salary from salaries where to_date = '9999-01-01' order by salary desc