sql server中嵌套事务*

时间:2024-09-06 11:35:50

转自 https://www.cnblogs.com/guanjie20/archive/2013/02/17/2914488.html

我们在写事务时经常遇到的问题如下:

消息 266,级别 16,状态 2,过程 sp1,第 0 行
EXECUTE 后的事务计数指示 BEGIN 和 COMMIT 语句的数目不匹配。上一计数 = 1,当前计数 = 0。
消息 3903,级别 16,状态 1,过程 sp2,第 15 行
ROLLBACK TRANSACTION 请求没有对应的 BEGIN TRANSACTION

如果这只是一个单独的事务引起的,那么很好解决,我们只要检查下是否遗漏了匹配的BEGIN tran 和 COMMIT tran即可,但是如果2个存储过程都是用事务写的,那么就即使每个存储过程的事务写法都正常,也会报这个错误,

这是因为只要子事务里有回滚语句:如ROLLBACK      那么全局的@@TRANCOUNT被直接置为0了,导致父事务提交时发现 @@TRANCOUNT=0  报错 ,sql server会认为当前不存在任何事务,在父存储过程中任何的COMMIT TRAN或

ROLLBACK 语句都会找不到它对应的 BEGIN TRAN

下面我们用一个实例来看下:

假设有一张表,ID为非自增主键

USE [TestDB]
GO /****** Object: Table [dbo].[test] Script Date: 02/17/2013 15:44:35 ******/
SET ANSI_NULLS ON
GO SET QUOTED_IDENTIFIER ON
GO SET ANSI_PADDING ON
GO CREATE TABLE [dbo].[test](
[ID] [bigint] NOT NULL,
[UserID] [bigint] NULL,
[Name] [varchar](50) NULL,
CONSTRAINT [PK_Table_1] PRIMARY KEY CLUSTERED
(
[ID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] GO SET ANSI_PADDING OFF
GO

我们常规的写一个插入的子存储过程如下:

USE [TestDB]
GO
/****** Object: StoredProcedure [dbo].[innertranv1] Script Date: 02/17/2013 15:46:46 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO --内层事务存储过程,演示如何处理才能在嵌套的事务存储过程中正确处理事务
ALTER PROCEDURE [dbo].[innertranv1]
@ID BIGINT ,
@UserID BIGINT ,
@Name VARCHAR(50)
AS
BEGIN
SET XACT_ABORT ON
BEGIN TRAN IF(EXISTS(SELECT TOP 1 * FROM dbo.test WHERE ID=@ID))
BEGIN
ROLLBACK
RETURN 0 ;
END --业务逻辑开始 INSERT dbo.test
( ID, UserID, Name)
VALUES ( @ID,
@UserID,
@Name
)
--业务逻辑结束 IF @@error <> 0
BEGIN
ROLLBACK
RETURN 0;
END COMMIT
     SET XACT_ABORT OFF;
     RETURN 1 ; END

调用的父存储过程如下:

USE [TestDB]
GO
/****** Object: StoredProcedure [dbo].[outertranv2] Script Date: 02/17/2013 16:09:09 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO -- =============================================
-- Author: <Author,,Name>
-- Create date: <Create Date,,>
-- Description: <外层存储过程>
-- =============================================
ALTER PROCEDURE [dbo].[outertranv2]
@ID BIGINT ,
@UserID BIGINT ,
@Name VARCHAR(50)
AS BEGIN TRAN
DECLARE @result INT
EXEC @result = innertranv1 @ID =@ID, @UserID =@UserID, @Name = @Name
IF ( @result <= 0 )
BEGIN
ROLLBACK TRAN ;
RETURN ;
END
COMMIT TRAN

我们执行父存储过程:

USE [TestDB]
GO DECLARE @return_value int EXEC @return_value = [dbo].[outertranv2]
@ID = 0,
@UserID = 0,
@Name = N'' SELECT 'Return Value' = @return_value GO

第一次提交正常,再次执行就会出现如下错误:

消息 266,级别 16,状态 2,过程 innertranv1,第 0 行
EXECUTE 后的事务计数指示 BEGIN 和 COMMIT 语句的数目不匹配。上一计数 = 1,当前计数 = 0。
消息 3903,级别 16,状态 1,过程 outertranv2,第 18 行
ROLLBACK TRANSACTION 请求没有对应的 BEGIN TRANSACTION。

如何解决?我们修改子存储过程如下:

USE [TestDB]
GO
/****** Object: StoredProcedure [dbo].[innertran] Script Date: 02/17/2013 16:26:26 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
--内层事务存储过程,演示如何处理才能在嵌套的事务存储过程中正确处理事务
ALTER PROCEDURE [dbo].[innertran]
@ID BIGINT ,
@UserID BIGINT ,
@Name VARCHAR(50)
AS
BEGIN
DECLARE @TRANCOUNT int=(select @@TRANCOUNT) SET XACT_ABORT ON
SET @TRANCOUNT=(select @@TRANCOUNT)
PRINT '未进入子事务前全局@@TRANCOUNT'+CAST(@TRANCOUNT AS VARCHAR(50))
BEGIN TRAN tran1 --开始事务
SAVE TRAN tranpoint --保存事务点
SET @TRANCOUNT=(select @@TRANCOUNT)
PRINT '进入子事务后全局@@TRANCOUNT'+CAST(@TRANCOUNT AS VARCHAR(50)) IF(EXISTS(SELECT TOP 1 * FROM dbo.test WHERE ID=@ID))
BEGIN
ROLLBACK TRAN tranpoint ; --回滚保存点的事务
COMMIT TRAN tran1 ; --提示当前事务
SET @TRANCOUNT=(select @@TRANCOUNT)
PRINT '回滚子事务后全局@@TRANCOUNT'+CAST(@TRANCOUNT AS VARCHAR(50)) RETURN 0 ;
END --业务逻辑开始 INSERT dbo.test
( ID, UserID, Name)
VALUES ( @ID,
@UserID,
@Name
)
--业务逻辑结束 IF @@error <> 0
BEGIN
ROLLBACK TRAN tranpoint ; --回滚保存点的事务
COMMIT TRAN tran1 ; --提示当前事务
SET @TRANCOUNT=(select @@TRANCOUNT)
PRINT '回滚子事务后全局@@TRANCOUNTT'+CAST(@TRANCOUNT AS VARCHAR(50)) RETURN 0;
END COMMIT TRAN tran1 ;
SET XACT_ABORT OFF;
SET @TRANCOUNT=(select @@TRANCOUNT)
PRINT '提交子事务后全局@@TRANCOUNT'+CAST(@TRANCOUNT AS VARCHAR(50)) RETURN 1 ; END

父过程如下:

USE [TestDB]
GO
/****** Object: StoredProcedure [dbo].[outertran] Script Date: 02/17/2013 16:27:13 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
-- =============================================
-- Author: <Author,,Name>
-- Create date: <Create Date,,>
-- Description: <外层存储过程>
-- =============================================
ALTER PROCEDURE [dbo].[outertran]
@ID BIGINT,
@UserID BIGINT,
@Name VARCHAR(50)
AS
DECLARE @TRANCOUNT int=(select @@TRANCOUNT)
PRINT '未进入父事务前全局@@TRANCOUNT:'+CAST(@TRANCOUNT AS VARCHAR(50)) BEGIN TRAN
SET @TRANCOUNT=(select @@TRANCOUNT)
PRINT '进入父事务后全局@@TRANCOUNT:'+CAST(@TRANCOUNT AS VARCHAR(50)) DECLARE @result INT EXEC @result = innertran @ID = @ID, @UserID = @UserID, @Name =@Name IF ( @result <= 0 )
BEGIN
ROLLBACK TRAN ;
SET @TRANCOUNT=(select @@TRANCOUNT)
PRINT '回滚父事务后全局@@TRANCOUNT:'+CAST(@TRANCOUNT AS VARCHAR(50)) RETURN ;
END
COMMIT TRAN
SET @TRANCOUNT=(select @@TRANCOUNT)
PRINT '提交父事务后全局@@TRANCOUNT:'+CAST(@TRANCOUNT AS VARCHAR(50))

调用父存储过程:

USE [TestDB]
GO DECLARE @return_value int EXEC @return_value = [dbo].[outertran]
@ID = 0,
@UserID = 0,
@Name = N'' SELECT 'Return Value' = @return_value GO

结果如下:

未进入父事务前全局@@TRANCOUNT:0
进入父事务后全局@@TRANCOUNT:1
未进入子事务前全局@@TRANCOUNT:1
进入子事务后全局@@TRANCOUNT:2
回滚子事务后全局@@TRANCOUNT:1
回滚父事务后全局@@TRANCOUNT:0

不会再报"EXECUTE 后的事务计数指示 BEGIN 和 COMMIT 语句的数目不匹配"之类的错误了,实际上就是在每个嵌套的子过程中标明当前事务点,每个子事务 只提交/回滚 子事务点,而不是回滚整个事务!

实际开发中还是会出现事务错乱的情况,如在try...catch...中