Question

您好我渴望得到帮助，因为我在复杂的逻辑查询上被困了两天，如果有人可以帮忙解决的话。

订购表

id           | region_id   | created_at | sale 
=============|=============|=========================
1            | 1           | 2011-09-21 |  $250
2            | 2           | 2012-03-12 |  $320
3            | 1           | 2010-09-15 |  $300
4            | 2           | 2011-08-18 |  $180
5            | 1           | 2012-04-13 |  $130
6            | 3           | 2010-06-22 |  $360
7            | 2           | 2011-09-25 |  $330

区域表

id           | region_name  
=============|=============
1            | Region 1          
2            | Region 2      
3            | Region 3

预期输出

我试图实现的目标

select distinct `regions`.`region_name`, sum(orders.sale) as sum, 
CASE WHEN MONTH(orders.created_at)>=4 THEN
concat(YEAR(orders.created_at), '-',YEAR(orders.created_at)+1)
ELSE concat(YEAR(orders.created_at)-1,'-', YEAR(orders.created_at)) 
END AS financial_year from `orders` inner join `regions` on `orders`.`region_id` = `regions`.`id` group by YEAR(orders.created_at), `regions`.`region_name` order by `orders`.`region_id` asc,  YEAR(orders.created_at) asc

我的查询输出

在查询中我的逻辑问题在哪里，有一件事应该在财务年度明智地提取，而不仅仅是正常的年份。

由于

Answer 1

http://sqlfiddle.com/#!9/16fdfb/9

只是为了修复您的查询，您不应该使用GROUP BY YEAR，因为您的财政年度与日历年度不匹配，并且因为您不希望在不同的行但列中输出不同的财务年度。您可以将查询转换为：

SELECT regions.region_name, 
    o.salePrev as `2010-11`,  
    o.saleCurrent as `2011-12`
FROM  (SELECT 
          region_id,
          SUM(IF(MONTH(orders.created_at)<4,sale,0)) salePrev,
          SUM(IF(MONTH(orders.created_at)>=4,sale,0)) saleCurrent
       FROM orders
       GROUP BY region_id
       ) o
INNER JOIN regions
ON o.region_id = regions.id;

但正如我在评论中提到的那样，你的条件MONTH(orders.created_at)<4与年份无关，我会将其转换为：

SELECT regions.region_name, 
    o.salePrev as `2010-11`,  
    o.saleCurrent as `2011-12`
FROM  (SELECT 
          region_id,
          SUM(IF(
                (MONTH(orders.created_at)<4 && YEAR(orders.created_at) = 2012)
                || YEAR(orders.created_at) < 2012
            ,sale,0)) salePrev,
          SUM(IF(MONTH(orders.created_at)>=4 && YEAR(orders.created_at) = 2012,sale,0)) saleCurrent
       FROM orders
       GROUP BY region_id
       ) o
INNER JOIN regions
ON o.region_id = regions.id;

但是，它不是按年份分组，只是将当前（2012-04 +）年份与过去几年（2012-04 - ）进行分组。

如果你需要所有年份......

更新 http://sqlfiddle.com/#!9/16fdfb/17

SELECT r.region_name, 
    SUM(IF(o.f_year=2010,o.y_sale,0)) as `2010-11`,  
    SUM(IF(o.f_year=2011,o.y_sale,0)) as `2011-12`,
    SUM(IF(o.f_year=2012,o.y_sale,0)) as `2012-13`
FROM  (SELECT 
          region_id,
          IF(MONTH(orders.created_at)<4,YEAR(created_at)-1,YEAR(created_at)) f_year,
          SUM(sale) y_sale
       FROM orders
       GROUP BY region_id, f_year
       ) o
INNER JOIN regions r
ON o.region_id = r.id
GROUP BY r.id

如何用条件语句实现mysql加入

1 个答案: