Question

我在股票部门的公司工作考虑两个出口和股票表，其中出口具有以下属性：

Export{
ExportDate Date not null,
StockID int not null,
Quantity decimal(10, 2),
};

和Stock表具有以下属性：

Stock{
ItemID int primary key,
ItemName nvarchar(MAX).
Exist decimal(15, 2)
};

因此，导出表格中的StockID是Stock表格中的ItemID引用，当导出表格中保存记录时，它还会根据导出表格中的stockID更新库存存量，导出表格中的VB.Net中的代码保存像这样的按钮：

Try
        cmd = New SqlCommand("INSERT INTO Export(ExportDate,StockID,Quantity) VALUES(@ExportDate, @StockID, @Quantity)", con)
        cmd.CommandTimeout = 1000
        cmd.CommandType = CommandType.Text
        cmd.Parameters.AddWithValue("@StockDate", dateTXT.Text)
        cmd.Parameters.AddWithValue("@StockID", comboStockID.SelectedValue)
        cmd.Parameters.AddWithValue("@Quantity", quantityTXT.Text)
        cmd.ExecuteNonQuery()
        MessageBox.show(“Stored”)

    Catch ex As Exception
        MessageBox.Show(“Not stored!” ex.Message)

    End Try





    'Updating stock Exist

        Try
        cmd = New SqlCommand("UPDATE Stock SET Exist = Exist - @quantity
         WHERE ItemID = '" & comboStockID.SelectedValue & "'", con)
        cmd.Parameters.AddWithValue("@quantity", qtyTXT.Text)
        cmd.ExecuteNonQuery()
 MessageBox.show(“Updated!”)

    Catch ex As Exception

        MessageBox.Show(ex.Message)
    End Try

假设在Stock表中的值如下：

ItemID      ItemName      Quantity
  105      Black color      300
  106      Green color      400

但是，当我加入它时，每行只显示300，它选择如下：

 ItemID      ItemName      Quantity
  105      Black color      300
  106      Green color      300

我想加入Exist of stock with Export table，并且在每次交易中它必须显示如下：

ExportDate      stockID     Quantity     Exist     
2017/8/24         105          5          295
2017/10/30        105         25          270

帮助我们，我该怎么做!!!

Answer 1

你可以使用windows函数，这是示例代码：

select exportdate, stockid, quantity, 
sum(pre_balance) over (partition by stockid order by exportdate) as exist  
from 
     (select exportdate, stockid, quantity, -quantity as pre_balance 
      from export 
      union
      select '2017-01-01' as exportdate, itemid as stockid, 
      0 as quantity, exist as pre_balance
      from stock 
      order by exportdate) as sub_query;

结果如下：

exportdate | stockid | quantity | exist  
------------+---------+----------+--------
 2017-01-01 |     105 |        0 | 300.00
 2017-08-24 |     105 |     5.00 | 295.00
 2017-10-30 |     105 |    25.00 | 270.00
 2017-01-01 |     106 |        0 | 400.00

表来源：

latihan=> select * from stock ;
 itemid |  itemname   | exist  
--------+-------------+--------
    105 | Black color | 300.00
    106 | Green color | 400.00
(2 rows)

latihan=> select * from export ;
 exportdate | stockid | quantity 
------------+---------+----------
 2017-08-24 |     105 |     5.00
 2017-10-30 |     105 |    25.00
(2 rows)

此链接是关于Windows功能的一个示例，但在印度尼西亚语和postgresql：

https://github.com/muntaza/Open_Persediaan/blob/master/perhitungan_saldo.md

这是google搜索链接：

https://www.google.com/search?q=windows+function+ms+sql

关于股票的链接，用英文：

https://callmeranjeet.wordpress.com/2014/09/01/calculating-stock-with-fifo-method-in-sql/

计算另一个表中每个事务中项的数量

1 个答案: