mysql-按天/月统计数据,没有的填充为0

本文主要是介绍mysql-按天/月统计数据,没有的填充为0，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

按天统计

1、创建基础表

CREATE TABLE num (i INT);
INSERT INTO num (i) VALUES (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);-- 测试表
DROP TABLE IF EXISTS `user`;
CREATE TABLE `user` (`id` int(11) NOT NULL AUTO_INCREMENT,`username` varchar(32) NOT NULL COMMENT '用户名称',`birthday` date DEFAULT NULL COMMENT '生日',`sex` char(1) DEFAULT NULL COMMENT '性别',`address` varchar(256) DEFAULT NULL COMMENT '地址',`sign_date` varchar(100) DEFAULT NULL,PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8;
INSERT INTO `user` VALUES ('1', '小南', '1991-04-04', '男', '湖南湘潭', '2018-03-13');
INSERT INTO `user` VALUES ('2', '小谭', '1981-01-27', '男', '湖南湘潭', '2018-03-12');
INSERT INTO `user` VALUES ('3', '小梅', '1981-04-28', '女', '广东梅县', '2018-04-14');
INSERT INTO `user` VALUES ('4', '小仪', '1986-04-12', '女', '四川仪陇', '2018-03-13');
INSERT INTO `user` VALUES ('5', '小蓝', '2001-01-01', '女', '上海嘉定', '2018-03-15');

2、查询时间范围

SELECTadddate('2018-03-01', numlist.id) AS 'date'FROM(SELECTn1.i + n10.i * 10 + n100.i * 100 AS idFROMnum n1CROSS JOIN num AS n10CROSS JOIN num AS n100) AS numlistWHEREadddate('2018-03-01', numlist.id) &lt;= date_add('2018-03-01',interval 1 month)

3、需要统计的数据

SELECT left(sign_date,10)as udate,count(sign_date) unmber FROM user GROUP BY udate

4、将上面两条语句一起查询(无值时补零)

SELECT temp.date,coalesce(u.unmber,0) 'number' from(SELECTadddate('2018-03-01', numlist.id) AS 'date'FROM(SELECTn1.i + n10.i * 10 + n100.i * 100 AS idFROMnum n1CROSS JOIN num AS n10CROSS JOIN num AS n100) AS numlistWHEREadddate('2018-03-01', numlist.id) &lt;= date_add('2018-03-01',interval 1 month)) temp
LEFT JOIN 
(SELECT left(sign_date,10)as udate,count(sign_date) unmber FROM user GROUP BY udate) u on temp.date = u.udate order by temp.date

查看结果集

按月统计差不多，上面的懂了，下面的是一样的

SELECT left(temp.date,7),coalesce(u.unmber,0) 'number' from(SELECT adddate('2018-01-01', interval numlist.id month) AS 'date' FROM (SELECT * from (SELECT n1.i + n10.i * 10 AS id FROM num n1 CROSS JOIN num AS n10) a where a.id&lt;=11) AS numlistWHERE adddate('2018-01-01', interval numlist.id month) &lt;= '2018-12-01') temp
LEFT JOIN 
(SELECT left(sign_date,7)as udate,count(sign_date) unmber FROM user GROUP BY udate) u on left(temp.date,7) = u.udate ORDER BY temp.date

查看结果