将多个子查询组合成一个查询

Posted 2023-05-09

【中文标题】将多个子查询组合成一个查询

【英文标题】：Combining multiple sub-queries into a single query

【发布时间】：2018-09-28 11:36:44

【问题描述】：

我正在尝试组合几个子查询以形成处于“进行中”状态的报告详细订单。长话短说，订单经历了多个阶段，客户希望在单位级别获得每个阶段的总库存。

这是我将前两个结合起来的尝试，我的想法是如果我做不到，我就无法添加另外两个。

select In_Progress_Total.purchase_order, In_Progress, In_Progress_Awaiting_Vas
from
(   select order_header.purchase_order, move_task.work_group,SUM(move_task.qty_to_move) AS In_Progress
    from move_task
    join order_header
    on move_task.task_id = order_header.order_id
    where move_task.site_id = 'USCOL1' and move_task.client_id = 'SDRY-US' and order_header.status = 'In Progress'
    group by order_header.purchase_order, move_task.work_group); as In_Progress_Total
join
(   select order_header.purchase_order, move_task.work_group, SUM(move_task.qty_to_move) AS In_Progress_Awaiting_Vas
    from move_task
    join order_header
    on move_task.task_id = order_header.order_id
    where move_task.site_id = 'USCOL1' and move_task.client_id = 'SDRY-US' and move_task.from_loc_id like 'DEPT%VAS' and order_header.status = 'In Progress'
    group by order_header.purchase_order, move_task.work_group); as Awaiting_Vas)
on In_Progress_Total.purchase_order = Awaiting_Vas.purchase_order
order by In_Progress_Total.purchase_order

当运行这两件事时，它将查询作为两个查询而不是一个查询运行，我收到以下错误（一旦解决会导致另一个）：

Multiple Queries / Error

另外两个要组合的查询：

select order_header.purchase_order, move_task.work_group,SUM(move_task.qty_to_move) AS In_Progress_Awaiting_Labels
from move_task
join order_header
on move_task.task_id = order_header.order_id
where move_task.site_id = 'USCOL1' and move_task.client_id = 'SDRY-US' and move_task.from_loc_id like 'OUTVAS' and order_header.status = 'In Progress'
group by order_header.purchase_order, move_task.work_group


select order_header.purchase_order, move_task.work_group,SUM(move_task.qty_to_move) AS Everything_Else
from move_task
join order_header
on move_task.task_id = order_header.order_id
where move_task.site_id = 'USCOL1' and move_task.client_id = 'SDRY-US' and order_header.status = 'In Progress' and move_task.from_loc_id not like '%OUTVAS%' and move_task.from_loc_id not like 'DEPT%VAS' 
group by order_header.purchase_order, move_task.work_group

非常感谢任何帮助。

【问题讨论】：

编辑您的问题并提供示例数据和所需的结果。

你可以使用相关子查询

【参考方案1】：

考虑使用条件聚合，将WHERE 条件移动到不同SUM 聚合的CASE 语句中。确保还使用表别名以提高可读性。

SELECT o.purchase_order, m.work_group,
       SUM(CASE 
               WHEN m.site_id = 'USCOL1' AND 
                    m.client_id = 'SDRY-US' AND 
                    o.status = 'In Progress'
               THEN m.qty_to_move
               ELSE NULL
           END) AS In_Progress,

       SUM(CASE 
               WHEN m.site_id = 'USCOL1' AND 
                    m.client_id = 'SDRY-US' AND 
                    m.from_loc_id LIKE 'DEPT%VAS' AND 
                    o.status = 'In Progress'
               THEN m.qty_to_move
               ELSE NULL
           END) AS In_Progress_Awaiting_Vas,

       SUM(CASE
               WHEN m.site_id = 'USCOL1' AND 
                    m.client_id = 'SDRY-US' AND 
                    m.from_loc_id LIKE 'OUTVAS' AND 
                    o.status = 'In Progress'
               THEN m.qty_to_move
               ELSE NULL
           END) AS In_Progress_Awaiting_Labels,

       SUM(CASE
               WHEN m.site_id = 'USCOL1' AND 
                    m.client_id = 'SDRY-US' AND 
                    o.status = 'In Progress' AND 
                    m.from_loc_id NOT LIKE '%OUTVAS%' AND 
                    m.from_loc_id NOT LIKE 'DEPT%VAS'
               THEN m.qty_to_move
               ELSE NULL
           END) AS Everything_Else

FROM move_task m
JOIN order_header o ON m.task_id = o.order_id 
GROUP BY o.purchase_order, m.work_group