MySQL排序_20160926

小程序：扫一扫查出行
【扫一扫了解最新限行尾号】
复制小程序

在工作中对数据进行排序也是最常用的,比如根据用户的下单金额降序或者对销售业绩进行降序排序在考核员工KPI时候也经常用到

一、order by 函数

order by 函数默认根据后面字段升序，使用降序使用

order by 字段名 desc写法

计算各城市各产品3个月份分别的订单额,以9月金额降序

SELECT city,productID,productname,SUM(IF(DATE_FORMAT(order_date,"%Y%m")=201607,pay_money,NULL)) AS 7月金额,
SUM(IF(DATE_FORMAT(order_date,"%Y%m")=201608,pay_money,NULL)) AS 8月金额,
SUM(IF(DATE_FORMAT(order_date,"%Y%m")=201609,pay_money,NULL)) AS 9月金额
FROM test_a03order
GROUP BY city,productID
ORDER BY SUM(IF(DATE_FORMAT(order_date,"%Y%m")=201609,pay_money,NULL)) DESC

2、order by field（）函数自定义排序

类似于excel中自定义排序一样 mysql也支持根据字段自定义排序

2.1SQL 让城市以city_A,city_C,city_B,city_D,city_E 这样的排序

对比2.2SQL 2.1SQL field 函数里面没有把city_F放到自定义顺序里面结果city_F默认置前这个在以后with rollup函数会用到

SELECT city,productID,productname,SUM(IF(DATE_FORMAT(order_date,"%Y%m")=201607,pay_money,NULL)) AS 7月金额,
SUM(IF(DATE_FORMAT(order_date,"%Y%m")=201608,pay_money,NULL)) AS 8月金额,
SUM(IF(DATE_FORMAT(order_date,"%Y%m")=201609,pay_money,NULL)) AS 9月金额
FROM test_a03order
GROUP BY city,productID
ORDER BY FIELD(city,"city_A","city_C","city_B","city_D","city_E")

2.2 SQL field 函数里面把city_F放到自定义顺序里面 city_F置于最后

SELECT city,productID,productname,SUM(IF(DATE_FORMAT(order_date,"%Y%m")=201607,pay_money,NULL)) AS 7月金额,
SUM(IF(DATE_FORMAT(order_date,"%Y%m")=201608,pay_money,NULL)) AS 8月金额,
SUM(IF(DATE_FORMAT(order_date,"%Y%m")=201609,pay_money,NULL)) AS 9月金额
FROM test_a03order
GROUP BY city,productID
ORDER BY FIELD(city,"city_A","city_C","city_B","city_D","city_E","city_F")