排序查詢(升序)

select 
      hiredate 
from 
      employees 
order by hiredate asc ;

排序查詢(降序)

select 
        hiredate 
from    employees 
order by hiredate desc ;

查詢員工信息，要求工資從高到低排序

select 
         *
from 
        employees  salary order by salary desc;

查詢部門編號 >= 90的員工信息，按入職時間的先后進行排序

select 
       * 
from  
        employees 
where department_id >= 90 order by hiredate asc ;

查詢 按年薪的高低顯示員工信息 和 年薪 （帶表達式的操作）

select 
         *,salary*12*(1+ifnull(commission_pct,0)) as "年薪"
from 
         employees
order by salary*12*(1+ifnull(commission_pct,0)) desc ;

查詢 按年薪的高低顯示員工信息 和 年薪 （按別名排序）

select 
         *,salary*12*(1+ifnull(commission_pct,0)) as "年薪"
from 
         employees
order by 年薪 desc ;

按姓名的長度顯示員工的姓名和工資【按函數排序】

select 
        last_name,salary,length(last_name) as "姓名長度"
from  
        employees
order by length(last_name) desc;

查詢員工信息，要求先按工資升序，再按員工編號降序序

注意：如果你排序的這兩列其中一列中有相同的數據的話
會導致另外一列排序的大小有大的在前面，如下圖：
select  
        salary,employee_id 
from 
        employees 
order by salary asc ,employee_id desc;

下面是練習題

• 1.查詢員工的姓名和部門號和年薪，按年薪降序，按姓名升序

select
        last_name as "姓名",
        department_id "部門號",
        salary*12*(1+ifnull(commission_pct,0)) as "年薪"
 from
        employees
 order by 年薪 desc,last_name asc;

• 2.查詢工資不在8000到17000的員工的姓名和工資，按工資降序排列；

select
       salary
from
     employees
where salary not between 8000 and 17000
order by salary desc;

• 3.查詢郵箱中包含e的員工信息，并且按郵箱的字節(jié)數降序，再按部門號升序

select
      *
from
      employees
where email like '%e%'
order by length(email) desc ,department_id asc ;