Question

我有两个表“ tbl_In_Details”和“ tbl_Out_Details” tbl_In_Details的示例数据

@code {
    Component1 c1 = new Component1();

  void SomeMethod()
  {
     c1.Tester();   // this should work
  }
}

现在我要计算当前库存，即（进货-出库）为Current_Stock 我以这种方式尝试过但没有得到正确的记录，请在需要修改查询的地方引导我：

sample data for tbl_In_Details

ID  Item_Name   Rate    Quantity    Source_company  
1   wire         10        4        2020-04-21 22:47:29.083 
2   Tea          4         20       2020-04-21 22:47:52.823

Sample data for tbl_Out_Details

ID  Item_Name   Quantity    Created_Date
1     wire        1       2020-04-21 22:48:48.233   
2     wire        2       2020-04-21 22:50:16.367   
3     Tea         2       2020-04-21 23:48:39.94

我的输出应该是

Select O.Item_Name, 
sum(CAST(I.Quantity AS INT))as Incomming_Quantity , 
 SUM(CAST(o.Quantity as int)) as Outgoing_Quantity , 
(sum(CAST(I.Quantity AS INT)) - SUM(CAST(o.Quantity AS INT))) As Current_Stock
from tbl_In_Details I inner join tbl_Out_Details O
ON I.Item_Name = o.Item_Name group by O.Item_Name

Answer 1

使用union all和聚合：

select item_name, sum(in_quantity) as in_quantity, sum(out_quantity) as out_quantity,
       sum(in_quantity) - sum(out_quantity) as in_stock
from ((select item_name, quantity as in_quantity, 0 as out_quantity
       from incoming
      ) union all
      (select item_name, 0, quantity 
       from outgoing
      ) 
     ) io
group by item_name;

如何从两个不同的表计算总和和减法

1 个答案: