mysql查询指定月份范围内，每个月的指定id下的数据量

Posted 2023-03-16

想获取指定book_id下的每月借阅次数。月份不存在该表时，数量为0有bookborrowing表和month表如上sql语句只能统计所有的分月数量，不能指定book_id。

SELECT DATE_FORMAT(m.month,'%Y-%m') AS `日期`, COUNT(b.book_id) AS 数目 FROM mon m LEFT JOIN book_borrowing b ON (DATE_FORMAT(m.month,'%Y-%m') = DATE_FORMAT(b.book_borrowingtime,'%Y-%m'))
GROUP BY m.month;

/*SQLyog Ultimate v11.24 (32 bit)mysql - 5.1.51-community **********************************************************************//*!40101 SET NAMES utf8 */;
create table `book_borrowing` ( `borrow_id` int (11), `u_id` varchar (243), `book_id` varchar (243), `book_stateid` varchar (54), `book_borrowingtime` date , `book_back` date , `book_returntime` date );
insert into `book_borrowing` (`borrow_id`, `u_id`, `book_id`, `book_stateid`, `book_borrowingtime`, `book_back`, `book_returntime`) values('1','240111516','12','5','2015-03-04','2015-06-13','2015-04-14');

/*SQLyog Ultimate v11.24 (32 bit)MySQL - 5.1.51-community **********************************************************************//*!40101 SET NAMES utf8 */;
create table `mon` ( `month` date ); insert into `mon` (`month`) values('2015-01-01');insert into `mon` (`month`) values('2015-02-01');insert into `mon` (`month`) values('2015-03-01');insert into `mon` (`month`) values('2015-04-01');insert into `mon` (`month`) values('2015-05-01');insert into `mon` (`month`) values('2015-06-01');

参考技术A 您好，
SELECT art_id, art_pdate
FROM ecos_article
WHERE art_id>75 limit 0,1
UNION
SELECT art_id, art_pdate
FROM ecos_article
WHERE art_id<=75 ORDER BY art_id DESC limit 0,3;
效果如下：
mysql> SELECT art_id, art_pdate FROM ecos_article limit 0,5;
+--------+------------+
| art_id | art_pdate |
+--------+------------+
| 73 | 2005-12-01 |
| 74 | 2005-12-01 |
| 75 | 2005-12-01 |
| 76 | 2005-12-01 |
| 77 | 2005-12-01 |
+--------+------------+

mysql> SELECT art_id, art_pdate
-> FROM ecos_article
-> WHERE art_id>75 limit 0,1
-> UNION
-> SELECT art_id, art_pdate
-> FROM ecos_article
-> WHERE art_id<=75 ORDER BY art_id DESC limit 0,3;
+--------+------------+
| art_id | art_pdate |
+--------+------------+
| 76 | 2005-12-01 |
| 75 | 2005-12-01 |
| 74 | 2005-12-01 |
+--------+------------+追问

不是这样的