Question

我已简化Entity Model以显示与我的问题相关的表格

我需要AFTER INSERT上的Packings触发器。

我希望它为dRoastedStocks INSERTED行Packings行中所选混合中包含的每种咖啡种类更新"NewOne" = "OldOne" - "Capacity of selected package" * "Ratio of CoffeeSort in selected Mix" * "Number of packages"表的相应行中的数量。

数量应按以下方式计算：

NewPacking

在这里，我已经使用Entity Framework在C＃中实现了它，并且它运行得很好，如果有人可以将它变成SQL Server触发器，我会非常感激

（//For each CoffeeSort included into selected Mix foreach (var mixDetail in NewPacking.Mix.Mix_Details) { // Find row in dRoastedStocks which refers to CoffeeSort var roastedStock = _context.dRoastedStocks.First(x => x.CoffeeSort.Id == mixDetail.CoffeeSort.Id); // Update it's quantity with new value by substracting packed quantity // Packed quantity is calculated as "Capacity of selected package" * "Ratio of CoffeeSort in selected Mix" * "Number of packages" roastedStock.Quantity -= NewPacking.PackQuantity * mixDetail.Ratio/100 * NewPacking.Package.Capacity; }指的是添加的行）

CREATE TRIGGER RoastedStocks_Insert_Packing
ON Packings
AFTER INSERT 
AS
    UPDATE dRoastedStocks
    SET dbo.dRoastedStocks.Quantity = 
          dbo.dRoastedStocks.Quantity - 
             (SELECT Ratio 
              FROM Mix_Details 
              WHERE Mix_Id = (SELECT INSERTED.Mix_Id FROM INSERTED)
                AND Mix_Details.CoffeeSort_Id = dRoastedStocks.CoffeeSort_Id) / 100
             * (SELECT INSERTED.PackQuantity FROM INSERTED)
             * (SELECT Capacity FROM Packages WHERE Id = (SELECT INSERTED.Package_Id FROM INSERTED))

解释起来非常复杂，所以我希望方案有所帮助

编辑：这是我尝试用SQL编写的内容，它与我之前编写的C＃几乎相同

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Answer 1

由于许多已发布的触发器在此处也未发现一次插入多行的情况。所有这些子查询都会以＆＃34;标量失败...但很多行返回＆＃34;错误。

看看这种方法：

UPDATE rs SET
  Quantity -= md.Ratio / 100 * i.PackQuantity * pk.Capacity
FROM INSERTED i
INNER JOIN dbo.Mix_Details md
   ON md.Mix_Id = i.Mix_Id
INNER JOIN dbo.Packages pk
   ON pk.Id = i.Package_Id
INNER JOIN dbo.dRoastedStocks rs
   ON rs.CoffeeSort_Id = md.CoffeeSort_Id

我需要帮助编写SQL Server触发器

1 个答案: