Question

我有一个如下表所示，初始插入将向“Cur_cost_unit”字段添加一个值，其中“Pre_cost_unit”默认值为0.当我将“Cur_cost_unit”更新为新值时，“Pre_cost_unit”需要用旧的“Cur_cost_unit”值更新，基本上成为“Cur_cost_unit”的历史值。我需要知道我的触发器是否会同时更新两个字段，“Cur_cost_unit”获取新值，Pre_cost_unit“获取”Cur_cost_unit“的历史值？

我的表：

create table [Prod_Cost]

(
[Ent_id]        int              not null    IDENTITY,
[Prod_name]     nvarchar(50)     not null,
[Prod_code]     nvarchar(50)     not null    UNIQUE,
[Prod_id]       int              not null    CONSTRAINT [PK_PRODUCT_ID] PRIMARY KEY,
[Cur_cost_unit] money            not null    DEFAULT(0),
[Pre_cost_unit] money            not null    DEFAULT(0),
[Dte_Captured]  datetime         not null,
[Captured_by]   char(50)         not null
);

我的触发器：

CREATE TRIGGER Update_Cur_CostUNIT_2PreV 
ON [Prod_Cost]

   AFTER UPDATE
AS 
DECLARE @Cur_cost_unit MONEY;
DECLARE @Prod_code NVARCHAR(50);

SELECT @Cur_cost_unit=i.[Cur_cost_unit] FROM inserted i;
SELECT @Prod_code = i.[Prod_code] from inserted i;

BEGIN

SET NOCOUNT ON;

    BEGIN
     UPDATE [Prod_Cost]
     SET [Pre_cost_unit] = (SELECT [Cur_cost_unit] FROM [Prod_Cost] where [Prod_code] = @Prod_code),
         [Cur_cost_unit] = @Cur_cost_unit
    END

END
GO

非常感谢提前

Answer 1

您可能正在寻找与此相似的更新

UPDATE  pc
SET     pc.Pre_cost_unit = d.Cur_cost_unit
FROM    [Prod_Cost] pc
        JOIN INSERTED i ON i.Ent_id = pc.Ent_id -- new values
        JOIN DELETED d ON d.Ent_id = i.Ent_id -- previous values

Answer 2

我想你可能想要一些（未经测试的）

CREATE TRIGGER Update_Cur_CostUNIT_2PreV 
ON [Prod_Cost]
   AFTER UPDATE
AS 
   UPDATE Prod_Cost
   SET Prod_Cost.Pre_cost_unit = deleted.Cur_cost_unit
   FROM Prod_Cost
   JOIN deleted
   ON Prod_Cost.Ent_id = deleted.Ent_id

Sql触发器将字段值“移动”到同一个表

2 个答案: