【數據庫】找出所有員工當前薪水salary情況

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題目描述

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找出所有員工當前(to_date=‘9999-01-01’)具體的薪水salary情況，對於相同的薪水只顯示一次,並按照逆序顯示
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));

思路：
可以用distinct或者goup by方法

代碼：

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

group by 方法
select salary from salaries where to_date='9999-01-01' group by salary order by salary DESC

**輸出描述: **