【原】[SQL Server] TRIGGER 触发器获得insert, delete, update行的信息

旧城等待， 2021-12-20 18:07 131阅读 0赞

一段trigger codes例子：

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][] 插入、删除和更新的触发器代码：   
\-- dbo.trGroups.SQL  
  
IFEXISTS (  
SELECT\*FROM sysobjects WHERE  
name ='trGroups'AND type ='TR')  
BEGIN  
DROPTRIGGER trGroups  
IFNOTEXISTS (  
SELECT\*FROM sysobjects WHERE  
name ='trGroups'AND type ='TR')  
PRINT'DROP trGroups SUCCEEDED'  
ELSE  
PRINT'DROP trGroups FAILED'  
END  
ELSE  
PRINT'Attempting to CREATE trGroups'  
GO  
  
CREATETRIGGER dbo.trGroups  
ON groups  
AFTER INSERT, UPDATE, DELETE  
AS  
  
\-- This trigger submits a cached rates delete job for modified groups.  
\-- It also updates the groups' last modified columns for modified groups.  
\-- It also updates the groups' state (if currently unspecified) based on   
\-- the (first) state extracted from groups' zip code for new/modified groups.  
\-- No error checking is currently being performed.  
  
SET NOCOUNT ON\-- stop display of rowcount messages  
  
DECLARE  
@groupIDint,  
@deletedCountint,  
@returnCodeint  
  
SELECT  
@deletedCount=COUNT(\*)  
FROM  
deleted WITH (NOLOCK)  
  
IF@deletedCount>**0**  
BEGIN  
DECLARE groupIDCursor CURSOR  
FAST\_FORWARD  
FOR  
SELECTDISTINCT  
t1.groupID  
FROM  
(  
SELECT  
groupID  
FROM  
inserted WITH (NOLOCK)  
  
UNION  
  
SELECT  
groupID  
FROM  
deleted WITH (NOLOCK)  
) as t1  
  
OPEN groupIDCursor  
  
FETCHNEXT  
FROM  
groupIDCursor  
INTO  
@groupID  
  
WHILE**@@FETCH\_STATUS**=**0**  
BEGIN  
EXEC@returnCode= dbo.spCachingModuleAddJobDeleteCachedRatesByGroupID  
@groupID=@groupID  
  
FETCHNEXT  
FROM  
groupIDCursor  
INTO  
@groupID  
END  
  
CLOSE groupIDCursor  
DEALLOCATE groupIDCursor  
END  
  
  
GO  
  
IFEXISTS (  
SELECT\*FROM sysobjects WHERE  
name ='trGroups'AND type ='TR')  
PRINT'CREATE trGroups SUCCEEDED'  
ELSE  
PRINT'CREATE trGroups FAILED'  
GO

触发器语句中使用了两种特殊的表：**deleted** 表和 **inserted** 表。  
Deleted 表用于存储 DELETE 和 UPDATE 语句所影响的行的复本。在执行 DELETE 或 UPDATE 语句时，行从触发器表中删除，并传输到 deleted 表中。Deleted 表和触发器表通常没有相同的行。

Inserted 表用于存储 INSERT 和 UPDATE 语句所影响的行的副本。在一个插入或更新事务处理中，新建行被同时添加到 inserted 表和触发器表中。Inserted 表中的行是触发器表中新行的副本。

1.插入操作（Insert）  
Inserted表有数据，Deleted表无数据  
  
2.删除操作（Delete）  
Inserted表无数据，Deleted表有数据  
  
3.更新操作（Update）  
Inserted表有数据（新数据），Deleted表有数据（旧数据）

转载于:https://www.cnblogs.com/luckylei66/archive/2009/02/27/1399397.html

[ContractedBlock.gif]: https://www.cnblogs.com/Images/OutliningIndicators/ContractedBlock.gif
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