加入表时得到错误的值？

Question

我的桌子是

Parent 我

WO     PRICE
1      1790    
1      9

Child 我

WO     PRICE
1      200    
1      400    
1      600
1      100

我正在尝试这样做

Select  sum(p.price), SUM(c.price) from Parent_WO p
left outer join Child_WO c
on p.WO= c.WO  
group by p.WO

我得到的 p.price 的值有误。我在 1796 年应该得到 7196。它是 parent WO 与 4 child WO 的总和。

Answer 1

尝试使用 2 CTE's；计算一个 CTE 中的 Parent 价格和另一个 CTE 中的 Child 价格并合并结果：

with parent_sum as (
  select
    wo
    ,SUM(price) as ParentSUM
  from parent_wo
  group by wo
)
,child_sum as (
  select
    wo
    ,SUM(price) as ChildSUM
  from child_wo
  group by wo
)
select
  p.wo
  ,ParentSUM
  ,ChildSUM
from parent_sum p
left join child_sum c
  on p.wo = c.wo

Answer 2

在之前进行聚合 sum():

Select coalesce(p.wo, c.wo) as wo, sum(p.price), SUM(c.price)
from (select p.wo, sum(p.price) as parent_price
      from Parent_WO p
      group by p.wo
     ) p full outer join
     (select c.wo, sum(c.price) as child_price
      from Child_WO c
      group by c.wo
     ) c
     on p.WO = c.WO ;

加入表时得到错误的值？

getting wrong values while joining tables?

sql

sql-server-2008-r2