Mysql进行数据分布统计经典专用SQL

版权声明：阅读优秀源码，宛若一场探索未知的旅行，疑惑处惊奇，优雅处旖旎; 一切都是新奇的，千回百转与大师的心灵触碰，一场跨越时空的对话，涤荡了原有的愚昧，蜕变出更好的自己。 https://blog.csdn.net/FENGQIYUNRAN/article/details/90761696

1. 数据库建表语句

[code]CREATE TABLE `start_duration` (
`id` bigint(13) NOT NULL AUTO_INCREMENT COMMENT '自增id',
`name` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NOT NULL COMMENT '事件名称',
`device_id` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NOT NULL COMMENT '设备id',
`country` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin DEFAULT NULL COMMENT '国家',
`start_time` int(11) NOT NULL DEFAULT '0' COMMENT '开始时间',
`duration` int(11) NOT NULL DEFAULT '0' COMMENT '时间间隔',
`create_time` datetime DEFAULT NULL COMMENT '创建时间',
`update_time` datetime DEFAULT NULL COMMENT '更新时间',
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8mb4

2. 统计 duration的数据分布

[code]SELECT
case when duration >0 and duration <500 then '1:(0,500)'
when duration >=500 and duration <1000 then '2:[500,1000)'
when duration >=1000 and duration <2000 then '3:[1000,2000)'
when duration >=2000 and duration <3000 then '4:[2000,3000)'
when duration >=3000 and duration <5000 then '5:[3000,5000)'
when duration >=5000 and duration <10000 then '6:[5000, 10000)'
when duration >=10000 and duration <20000 then '7:[10000, 20000)'
when duration >=20000 then '8:[20000+)'
ELSE '1:(0,500)' END 'duration(ms)',
COUNT(*) 'count'
FROM  start_duration
WHERE create_time > '2019-06-01 00:00:00'
GROUP BY
case when duration >0 and duration <500 then '1:(0,500)'
when duration >=500 and duration <1000 then '2:[500,1000)'
when duration >=1000 and duration <2000 then '3:[1000,2000)'
when duration >=2000 and duration <3000 then '4:[2000,3000)'
when duration >=3000 and duration <5000 then '5:[3000,5000)'
when duration >=5000 and duration <10000 then '6:[5000, 10000)'
when duration >=10000 and duration <20000 then '7:[10000, 20000)'
when duration >=20000 then '8:[20000+)'
ELSE '1:(0,500)' END

3. 统计执行结果

[code]+------------------+-------+
| duration(ms)     | count |
+------------------+-------+
| 1:(0,500)        | 14896 |
| 2:[500,1000)     | 12847 |
| 3:[1000,2000)    | 11132 |
| 4:[2000,3000)    |  4603 |
| 5:[3000,5000)    |  1459 |
| 6:[5000, 10000)  |  449 |
| 7:[10000, 20000) |  204 |
| 8:[20000+)       |  156 |
+------------------+-------+

分析：在每个分布的字段前面天机  “数字:” 格式可以充分利用，mysql的自动排序功能，使数据展现更美观整齐