题解 | #查找所有员工的last_name和first_name以及对应部门编号dept_no#
找出所有员工当前薪水salary情况
http://www.nowcoder.com/practice/ae51e6d057c94f6d891735a48d1c2397
select distinct salary from salaries order by salary desc; 或者 select salary from salaries group by salary order by salary desc;