mysql滑动聚合
滑动聚合是按顺序对滑动窗口范围内的数据进行聚合的操作。下累积聚合不同,滑动聚合并不是统计开始计算的位置到当前位置的数据。
SELECT
a.empid,
DATE_FORMAT(a.ordermonth, '%Y-%m') AS ordermonth,
a.qty AS thismonth,
SUM(b.qty) AS total,
CAST(AVG(b.qty) AS DECIMAL(5,2)) AS avg
FROM emporders a
INNER JOIN emporders b
ON a.empid=b.empid
AND b.ordermonth > DATE_ADD(a.ordermonth, INTERVAL -3 MONTH)
AND b.ordermonth <= a.ordermonth
WHERE DATE_FORMAT(a.ordermonth,'%Y')='2015' AND DATE_FORMAT(b.ordermonth,'%Y')='2015'
GROUP BY a.empid,DATE_FORMAT(a.ordermonth, '%Y-%m'),a.qty
ORDER BY a.empid,a.ordermonth
SELECT
a.empid,
a.ordermonth AS ordermonth,
a.qty AS thismonth,
SUM(b.qty) AS total,
CAST(AVG(b.qty) AS DECIMAL(5,2)) AS avg
FROM emporders a
INNER JOIN emporders b
ON a.empid=b.empid
AND b.ordermonth > DATE_ADD(a.ordermonth, INTERVAL -3 MONTH)
AND b.ordermonth <= a.ordermonth
WHERE DATE_FORMAT(a.ordermonth,'%Y')='2015' AND DATE_FORMAT(b.ordermonth,'%Y')='2015' AND a.empid=1
GROUP BY a.empid,DATE_FORMAT(a.ordermonth, '%Y-%m'),a.qty
HAVING MIN(b.ordermonth)=DATE_ADD(a.ordermonth, INTERVAL-2 MONTH)
ORDER BY a.empid,a.ordermonth
运行结果如下
aaarticlea/png;base64,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" alt="" />
mysql滑动聚合的更多相关文章
- MySQL数据库聚合函数
+++++++++++++++++++++++++++++++++++++++++++标题:MySQL数据库聚合函数时间:2019年2月25日内容:MySQL数据库聚合函数重点:MySQL数据库聚合函 ...
- MySQL之聚合数据(AVG,COUNT,MAX,MIN,SUM)
1.首先我们需要了解下什么是聚合函数 聚合函数aggregation function又称为组函数. 认情况下 聚合函数会对当前所在表当做一个组进行统计. 2.聚合函数的特点 1.每个组函数接收一个参 ...
- MySQL 排错-解决MySQL非聚合列未包含在GROUP BY子句报错问题
排错-解决MySQL非聚合列未包含在GROUP BY子句报错问题 By:授客 QQ:1033553122 测试环境 win10 MySQL 5.7 问题描述: 执行类似以下mysql查询, SEL ...
- MySQL的聚合函数
MySQL的聚合函数 网站:https://www.runoob.com/mysql/mysql-functions.html 函数名 功能描述 count() 计数 sum() 求和 avg() 平 ...
- Over:窗口函数(滑动聚合)
Over 窗口函数在Select 子句中,对查询的结果集进行“滑动-聚合”运算:如果使用count,那么基于滑动窗口的聚合语义同 base+1 累加:如果使用sum,那么基于滑动窗口的聚合语义等同于数 ...
- mysql 从聚合函数group by到sql_mode
说到group by, 想必大家都不陌生, 就是对查询的数据进行分组,我们可以通过该操作实现一些特殊需求,比如去重. 最近在项目中使用HQL:" from TSjrz where CBh = ...
- mysql连续聚合
连续聚合是按时间顺序对有序数据进行聚合的操作. 在下面的救示例中将使用EmpOrders表,该表用于存放每位员工每月发生的订购数量. 运行如下 代码创建EmpOrders表并填充示例数据. CREAT ...
- Mysql 分组聚合实现 over partition by 功能
mysql中没有类似oracle和postgreSQL的 OVER(PARTITION BY)功能. 那么如何在MYSQL中搞定分组聚合的查询呢 先说结论: 利用 group_concat + sub ...
- MySQL分组聚合group_concat + substr_index
场景:给予一张商品售卖表,表中数据为商品的售卖记录,假设表中数据是定时脚本插入的,每个时间段的商品售卖数量不同,根据此表找各个商品的最多售卖数量的数据. 1.数据表 CREATE TABLE `goo ...
随机推荐
- 关于chrome密码保存框的神坑,这样子解决就行
- spo0lsv病毒分析
1.样本概况 1.1 样本信息 病毒名称:spo0lsv.exe 所属家族:Worm MD5值:512301C535C88255C9A252FDF70B7A03 SHA1值:CA3A1070CFF31 ...
- Java中十六进制转换 Integer.toHexString()
为了显示一个byte型的单字节十六进制(两位十六进制表示)的编码,请使用: Integer.toHexString((byteVar & 0x000000FF) | 0xFFFFFF00).s ...
- php实现最简单的MVC框架实例教程
本文以一个实例的形式讲述了PHP实现MVC框架的过程,比较浅显易懂.现分享给大家供大家参考之用.具体分析如下: 首先,在学习一个框架之前,基本上我们都需要知道什么是mvc,即model-view-co ...
- Thread,ThreadPool,Task
线程分为前台和后台.比如我们直接new一个Thread这就是前台线程. 前台线程一定会执行. 比如我们创建2个线程:1号,2号,同时执行,假设1号是主线程,1执行完了,依旧会等待2执行完成,整个程序才 ...
- Python序列结构--集合
集合:元素之间不允许重复 集合属于Python无序可变序列,元素之间不允许重复 集合对象的创建与删除 直接将值赋值给变量即可创建一个集合 >>> a = {3,5}>>& ...
- iptables log日志记录功能扩展应用:iptables自动配置临时访问策略,任意公网登录服务器
一.修改日志记录: 1. 修改配置文件: vi /etc/rsyslog.conf 添加以下内容 #iptables log kern.=notice /var/log/iptables.log 2. ...
- 最小化安装的centos7.5上编译安装git2.19
VMware Workstation已经采用最小化安装CentOS7,显示版本为CentOS7.5,准备采用yum安装git. 采用yum list git发现可安装的GIT软件包版本1.8.3.1, ...
- Asp.Net WebAPI核心对象解析(三)
对于.NET的分布式应用开发,可以供我们选择的技术和框架比较多,例如webservice,.net remoting,MSMQ,WCF等等技术.对于这些技术很多人都不会陌生,即时没有深入的了解,但是肯 ...
- HTTP 协议常见首部字段
首部字段 1.HTTP协议的请求和响应报文中必定包含HTTP首部.首部内容为客户端和服务器处理请求和响应提供了所必须的信息. 2.HTTP首部字段是由首部字段名和字段值构成,中间用冒号“:”隔开.字段 ...