我们如何在SQL Server 2012中的触发器中使用会话值并插入表中？ [英] How can we use session value in trigger in SQL server 2012 and insert into a table?

问题描述

How can we use session value in trigger in SQL Server 2012 and insert into a table? I created a session but getting confuse, how can i use session value into a trigger. I'm creating a log table for view all logs that which action is acted in main table. and please tell me how can I update table with update Trigger with new session value and ID fetch from main table to update data. In given code @ActionBy value I want from new session.
How can I do this? Please let me know about this.

我尝试过的事情：

What I have tried:

CREATE TRIGGER EpaperTrgrUpdate
       ON EPaper
AFTER INSERT
AS
BEGIN
       SET NOCOUNT ON;
 
       DECLARE @EpaperId INT
	   DECLARE @Date datetime
	   DECLARE @ActionBy nvarchar(50)
	   DECLARE @Action varchar(50)
 
       SELECT @EpaperId = EPaper.SrNo, @Date = date, @ActionBy = EPaper.ActionBy      
       FROM EPaper
 
	   IF UPDATE(IMG)
       BEGIN
              SET @Action = 'Image Updated'
       END
 
       IF UPDATE(Date)
       BEGIN
              SET @Action = 'Date Updated'
       END

       INSERT INTO Epaper_Log
       VALUES(@EpaperId, @Date, @Action, @ActionBy)
END

推荐答案

你不能。您可以访问INSERTED和DELETED表，因此您必须先向其中一个表添加一个列并先设置它，然后您可以在触发器中读取它。



此外，写入触发器的方式不是编写触发器的好方法，因为它一次只能用于1条记录。如果您一次插入多个记录，则此触发器将不起作用。



实际上，这甚至不适用于单个记录，因为你没有限定你的WHERE子句，这意味着你将获得最后的记录取决于如何SQL读取表EPaper。

You can't. You do have access to the INSERTED and DELETED tables so you would have to add a column to one of the tables and set it first and then you could read it in the trigger.

Also, the way your trigger is written is not a good way to write triggers because it only works for 1 record at a time. If you ever insert more than one record at a time this trigger will not work.

In fact, this won't even work for a single record because you don't qualify your WHERE clause which means you'll get the last record depending on how SQL reads in the table EPaper.

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