Question

我有这个过程，它将记录从一个表插入另一个表。目标表具有名为LeadId

的标识列


Create Procedure prcInsertPrd
 As
  Begin
   Begin Transaction 
     Declare @Identity int
     Insert into Temp_ProductsArchive (column1,column2,column3)  select   
       (column1,column2,column3) 
    from Temp_Products

   if(@@Error=0)
     Begin
       Commit  
     End
   else
     Begin
       Rollback
     End
  End

然后我写了一个Insert Trigger，它将从插入的表中获取LeadId并将其插入另一个表中，其他值为 -


Alter TRIGGER trgInsertTopProducts
   ON  Temp_ProductsArchive
   AFTER INSERT
AS 
BEGIN
    -- SET NOCOUNT ON added to prevent extra result sets from
    -- interfering with SELECT statements.
    SET NOCOUNT ON;
     declare @LeadId as int
     Select @LeadId=LeadId from inserted 
     print @LeadId

Insert into Temp_ProductsTop(column4,LeadID,Column5,column6) Select column4,@LeadID 'LeadID',column 5,column6 from Temp_Products
END
GO

问题是我得到的第一个生成的LeadiD并非所有LeadIds。 Temp_ProductsTop表中的LeadiD列仅对记录数重复此值

Answer 1

您的触发器存在严重问题。编写触发器时，必须假定它可能被多行调用。即inserted表可能包含多行，这意味着您必须加入到插入的表中。

我不确定你要在代码中实现什么，但是你需要重写这样的东西：

   Alter TRIGGER trgInsertTopProducts  
    ON  Temp_ProductsArchive 
    AFTER INSERT AS
    BEGIN    
      SET NOCOUNT ON;    
      insert into Temp_ProductsTop 
        (ProductID,LeadID,ProductName,SupplierID,CategoryID,QuantityPerUnit,UnitPrice,UnitsInStock,UnitsOnOrder,ReorderLevel,Discontinued) 
      Select ProductID, inserted.LeadID, ProductName,SupplierID,CategoryID,QuantityPerUnit,UnitPrice,UnitsInStock,UnitsOnOrder,ReorderLevel,Discontinued 
      from 
        Temp_Products
        inner join inserted on inserted.Leadid = ?
    END

GO

在哪里？代表你加入的table.column。您想为每个LeadId添加temp_products吗？

Answer 2

“inserted”是一个伪插入，包含插入的每个项目的行。触发器仅触发一次总计，而不是每次插入一次！

您可能需要使用游标循环插入的记录，一次处理一个。也许：

Alter TRIGGER trgInsertTopProducts
  ON Temp_ProductsArchive
  AFTER INSERT
AS
BEGIN
  -- SET NOCOUNT ON added to prevent extra result sets from
  -- interfering with SELECT statements.
  SET NOCOUNT ON;
  declare @LeadId as int
  declare c CURSOR READ_ONLY for
    select LeadId from inserted

  open c
  fetch next from c into @LeadId
  while @@FETCH_STATUS = 0
  BEGIN
    Insert into Temp_ProductsTop(ProductID,LeadID,ProductName,SupplierID,CategoryID,QuantityPerUnit,UnitPrice,UnitsInStock,UnitsOnOrder,ReorderLevel,Discontinued) Select ProductID,@LeadID 'LeadID',ProductName,SupplierID,CategoryID,QuantityPerUnit,UnitPrice,UnitsInStock,UnitsOnOrder,ReorderLevel,Discontinued from Temp_Products
    fetch next from c into @LeadId
  END
  close c
  deallocate c
END

（请注意，我刚刚在此处输入此内容并且未进行语法检查或测试）

如何获取标识值列 - SQL

2 个答案: