两个并行查询-共有月/年（MYSQL）

我试图将两个查询并排放置，它们之间有相同的月份和年份。 他们各自工作得很好

表框-每月查找表框

SELECT count(*) AS Count_Boxes,
DATE_FORMAT(create_date, '%b') AS 'Month',
DATE_FORMAT(create_date, '%Y') AS 'Year'
FROM boxes
GROUP BY YEAR(create_date), MONTH(create_date);

SELECT count(*) as Count_Orders,
DATE_FORMAT(create_date, '%b') AS 'Month',
DATE_FORMAT(create_date, '%Y') AS 'Year'
FROM orders
GROUP BY YEAR(create_date), MONTH(create_date);

表订单-每月查找订单

SELECT count(*) AS Count_Boxes,
DATE_FORMAT(create_date, '%b') AS 'Month',
DATE_FORMAT(create_date, '%Y') AS 'Year'
FROM boxes
GROUP BY YEAR(create_date), MONTH(create_date);

SELECT count(*) as Count_Orders,
DATE_FORMAT(create_date, '%b') AS 'Month',
DATE_FORMAT(create_date, '%Y') AS 'Year'
FROM orders
GROUP BY YEAR(create_date), MONTH(create_date);

我尝试了很多使用左连接的方法，但都没有效果

有什么建议吗？

您可以加入：

SELECT o.count_orders, b.*
FROM (
    SELECT count(*) AS Count_Boxes,
    DATE_FORMAT(create_date, '%b') AS mn,
    DATE_FORMAT(create_date, '%Y') AS yr
    FROM boxes
    GROUP BY YEAR(create_date), MONTH(create_date)
) b
INNER JOIN (
    SELECT count(*) as Count_Orders,
    DATE_FORMAT(create_date, '%b') AS mn,
    DATE_FORMAT(create_date, '%Y') AS yr
    FROM orders
    GROUP BY YEAR(create_date), MONTH(create_date)
) o ON o.mn = b.mn and o.yr = o.yr

但是，如果其中任何一个数据集都可能缺少周期，则另一种方法使用

union all

：

SELECT 
    SUM(no_orders) count_orders,
    SUM(no_boxes) count_boxes,
    DATE_FORMAT(create_date, '%b') mn,
    DATE_FORMAT(create_date, '%Y') yr
FROM (
    SELECT create_date, 0 no_orders, 1 no_boxes FROM boxes
    UNION ALL       
    SELECT create_date, 1, 0 FROM orders
)
GROUP BY YEAR(create_date), MONTH(create_date)

请给出你所需要的&把它和你的问题联系起来。仅将图像用于无法表示为文本或扩充文本的内容。请在代码问题中给出--cut&paste&runnable代码，包括作为代码输入的最小代表性示例；期望和实际输出（包括逐字记录错误消息）；标签和版本；清晰的说明和解释。对于包含DBMS和DDL（包括约束和索引）的SQL，请将其输入为格式化为表的代码。