CLR 事务示例
此示例说明如何使用 System.Transactions 命名空间中的托管 API 来控制事务。 特别需要指出的是，System.Transactions.TransactionScope 类用于建立事务边界，以确保只有在库存足以满足需求的情况下才调整库存数据，而且如果存在足够的库存，库存将以原子方式从一个位置传输到另一个位置。 通过将库存中的更改记录到存储在独立 SQL Server 实例上的审核数据库来说明如何在分步式事务中进行自动注册。
先决条件
若要创建和运行此项目，必须安装下列软件：
SQL Server 或 SQL Server Express。 您可以从 SQL Server Express Documentation and Samples （Express 文档和示例）网站免费获取 SQL Server Express。
SQL Server 开发人员网站提供的 AdventureWorks 数据库
.NET Framework SDK 2.0 或更高版本，或 Microsoft Visual Studio 2005 或更高版本。 您可以免费获取 .NET Framework SDK。
此外，还必须满足以下条件：
您使用的 SQL Server 实例必须已启用 CLR 集成。
若要启用 CLR 集成，请执行以下步骤：
启用 CLR 集成
- 执行以下 Transact-SQL 命令：
sp_configure 'clr enabled', 1
GO
RECONFIGURE
GO
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注意若要启用 CLR，您必须具有 ALTER SETTINGS 服务器级别权限，sysadmin 和 serveradmin 固定服务器角色的成员隐式拥有该权限。
必须在您使用的 SQL Server 实例上安装 AdventureWorks 数据库。
如果您不是要使用的 SQL Server 实例的管理员，则必须让管理员授予您 CreateAssembly 权限，才能完成安装。
生成示例
按照以下说明创建和运行该示例：
打开 Visual Studio 或 .NET Framework 命令提示符。
如有必要，为您的示例创建目录。 对于此示例，我们将使用 C:\MySample。
由于此示例需要签名的程序集，请通过键入以下命令创建一个非对称密钥：
sn -k SampleKey.snk
从命令行提示符执行以下代码之一（具体取决于所选的语言)，对示例代码进行编译。
Vbc /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\v3.5\System.Core.dll","C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\v3.5\System.Data.DataSetExtensions.dll","C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.Data.dll","C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.dll","C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.Transactions.dll","C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.Xml.dll" /keyfile:Key.snk /target:Library /out:Transaction.dll InventoryMover.vb
Csc /reference:C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.Data.dll /reference:C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.dll /reference:C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.Transactions.dll /reference:C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.Xml.dll /keyfile:key.snk /out:Transaction.dll /target:library InventoryMover.cs
将 Transact-SQL 安装代码复制到一个文件中，并在示例目录中将其另存为 install.sql。
通过执行以下命令部署程序集和存储过程：
- sqlcmd -E -I -i install.sql -v root = "C:\MySample\"
将 Transact-SQL 数据库安装代码复制到一个文件中，并在示例目录中将其另存为 installDB.sql。
通过执行以下命令安装审核数据库：
- Sqlcmd –S server_name [ \instance_name ] -E -I -i installDB.sql
（需为实例和服务器提供适当的值。）
将 Transact-SQL 测试命令脚本复制到一个文件中，并在示例目录中将其另存为 test.sql。
使用以下命令执行测试脚本：
- sqlcmd -E -I -i test.sql
将 Transact-SQL 数据库清除脚本复制到一个文件中，并在示例目录中将其另存为 cleanupDB.sql。
使用以下命令执行该脚本：
Sqlcmd –S server_name [ \instance_name ] -E -I -i cleanup.sql
（需为实例和服务器提供适当的值。）
将 Transact-SQL 清除脚本复制到一个文件中，并在示例目录中将其另存为 cleanup.sql。
使用以下命令执行该脚本：
- sqlcmd -E -I -i cleanup.sql
示例代码
下面是此示例的代码列表。
C#
using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.SqlTypes;
using System.Data.SqlClient;
using System.Transactions;
using Microsoft.SqlServer.Server;
using System.Security.Principal;
public static class InventoryMover
{
const string contextConnectionString = "context connection=true";
// **********
// Important: Change this connection string to refer to a server other than the one
// you have installed the AdventureWorks database. This sample demonstrates
// two-phase commit across multiple servers, and loopback to the same server is not
// permitted from CLR integrated based stored procedures.
// **********
const string auditConnectionString = "server=<YourServer>; database=InventoryAudit; user=<YourUser>; password=<YourPassword>";
[SqlMethod(DataAccess = DataAccessKind.Read, IsMutator = true)]
public static void ExecuteTransfer(int productID, short fromLocationID,
short toLocationID, short quantityToTransfer)
{
// Establish bounds of the transaction
using (TransactionScope transScope = new TransactionScope())
{
using (SqlConnection adventureworksConnection = new
SqlConnection(contextConnectionString))
{
// Opening adventureworksConnection automatically enlists it in the
// TransactionScope as part of the transaction.
adventureworksConnection.Open();
SqlCommand checkCommand = adventureworksConnection.CreateCommand();
checkCommand.CommandText = "SELECT TOP 1 Quantity"
+ " FROM Production.ProductInventory WITH (REPEATABLEREAD)"
+ " WHERE ProductID = @ProductID AND LocationID = @LocationID;";
checkCommand.Parameters.Add("@ProductID", SqlDbType.Int);
checkCommand.Parameters[0].Value = productID;
checkCommand.Parameters.Add("@LocationID", SqlDbType.Int);
checkCommand.Parameters[1].Value = fromLocationID;
object result = checkCommand.ExecuteScalar();
short availableQuantity = (short)result;
if (availableQuantity < quantityToTransfer)
//It would be better to throw a custom error, and in some cases to actually
//RAISERROR. Also, it would be better to map product IDs and location IDs to
//names for the error message.
throw new ArgumentOutOfRangeException("quantityToTransfer",
string.Format("Attempt to transfer {0} of product {1} from"
+ " location {2} but only {3} is available.",
quantityToTransfer, productID, fromLocationID,
availableQuantity));
//Remove inventory count from source
SqlCommand reduceCommand = adventureworksConnection.CreateCommand();
reduceCommand.CommandText = "UPDATE Production.ProductInventory"
+ " SET Quantity = Quantity - @QuantityToTransfer"
+ " WHERE ProductID = @ProductID AND LocationID = @LocationID;";
reduceCommand.Parameters.Add("@ProductID", SqlDbType.Int);
reduceCommand.Parameters[0].Value = productID;
reduceCommand.Parameters.Add("@LocationID", SqlDbType.SmallInt);
reduceCommand.Parameters[1].Value = fromLocationID;
reduceCommand.Parameters.Add("@QuantityToTransfer", SqlDbType.SmallInt);
reduceCommand.Parameters[2].Value = quantityToTransfer;
reduceCommand.ExecuteNonQuery();
//Increate inventory count at destination
SqlCommand increaseCommand = adventureworksConnection.CreateCommand();
increaseCommand.CommandText = "UPDATE Production.ProductInventory"
+ " SET Quantity = Quantity + @QuantityToTransfer"
+ " WHERE ProductID = @ProductID AND LocationID = @LocationID;";
increaseCommand.Parameters.Add("@ProductID", SqlDbType.Int);
increaseCommand.Parameters[0].Value = productID;
increaseCommand.Parameters.Add("@LocationID", SqlDbType.SmallInt);
increaseCommand.Parameters[1].Value = toLocationID;
increaseCommand.Parameters.Add("@QuantityToTransfer", SqlDbType.SmallInt);
increaseCommand.Parameters[2].Value = quantityToTransfer;
increaseCommand.ExecuteNonQuery();
// Create an audit trail of the inventory transfer. We must impersonate the
// client credentials in order for this to work. Otherwise we'd have to
// set up security for the machine account.
// SqlConnection auditConnection = adventureworksConnection;
using (SqlConnection auditConnection = new SqlConnection(auditConnectionString))
{
SqlCommand auditCommand = auditConnection.CreateCommand();
auditCommand.CommandText = "INSERT InventoryChange "
+ " (ProductID, FromLocationID, ToLocationID, Quantity) "
+ " VALUES (@ProductID, @FromLocationID, @ToLocationID, @Quantity);";
auditCommand.Parameters.Add("@ProductID", SqlDbType.Int);
auditCommand.Parameters[0].Value = productID;
auditCommand.Parameters.Add("@FromLocationID", SqlDbType.SmallInt);
auditCommand.Parameters[1].Value = fromLocationID;
auditCommand.Parameters.Add("@ToLocationID", SqlDbType.SmallInt);
auditCommand.Parameters[2].Value = toLocationID;
auditCommand.Parameters.Add("@Quantity", SqlDbType.SmallInt);
auditCommand.Parameters[3].Value = quantityToTransfer;
// Opening auditConnection automatically enlists it in the
// TransactionScope as part of the transaction.
auditConnection.Open();
auditCommand.ExecuteNonQuery();
}
}
// The Complete method commits the transaction.
transScope.Complete();
}
}
}
Visual Basic
Imports System
Imports System.Collections.Generic
Imports System.Text
Imports System.Data
Imports System.Data.SqlTypes
Imports System.Data.SqlClient
Imports System.Transactions
Imports Microsoft.SqlServer.Server
Imports System.Security.Principal
Imports System.Globalization
Public NotInheritable Class InventoryMover
Private Const contextConnectionString As String = "context connection=true"
Private Sub New()
End Sub
' **********
' Important: Change this connection string to refer to a server other than the one
' you have installed the AdventureWorks database. This sample demonstrates
' two-phase commit across multiple servers, and loopback to the same server is not
' permitted from CLR integrated based stored procedures.
' **********
Private Const auditConnectionString As String = "server=<YourServer>; database=InventoryAudit; user=<YourUser>; password=<YourPassword>"
<SqlMethod(DataAccess:=DataAccessKind.Read, IsMutator:=True)> _
Public Shared Sub ExecuteTransfer(ByVal productID As Integer, ByVal fromLocationID As Short, _
ByVal toLocationID As Short, ByVal quantityToTransfer As Short)
' Establish bounds of the transaction
Using transScope As New TransactionScope()
Using adventureworksConnection As New SqlConnection(contextConnectionString)
' Opening adventureworksConnection automatically enlists it in the
' TransactionScope as part of the transaction.
adventureworksConnection.Open()
Dim checkCommand As SqlCommand = adventureworksConnection.CreateCommand()
checkCommand.CommandText = "SELECT TOP 1 Quantity" _
& " FROM Production.ProductInventory WITH (REPEATABLEREAD)" _
& " WHERE ProductID = @ProductID AND LocationID = @LocationID;"
checkCommand.Parameters.Add("@ProductID", SqlDbType.Int)
checkCommand.Parameters(0).Value = productID
checkCommand.Parameters.Add("@LocationID", SqlDbType.Int)
checkCommand.Parameters(1).Value = fromLocationID
Dim result As Object = checkCommand.ExecuteScalar()
Dim availableQuantity As Short = CType(result, Short)
If (availableQuantity < quantityToTransfer) Then
'It would be better to throw a custom error, and in some cases to actually
'RAISERROR. Also, it would be better to map product IDs and location IDs to
'names for the error message.
Throw New ArgumentOutOfRangeException("quantityToTransfer", _
String.Format(CultureInfo.InvariantCulture, "Attempt to transfer {0} of product {1} from" _
& " location {2} but only {3} is available.", _
quantityToTransfer, productID, fromLocationID, _
availableQuantity))
End If
'Remove inventory count from source
Dim reduceCommand As SqlCommand = adventureworksConnection.CreateCommand()
reduceCommand.CommandText = "UPDATE Production.ProductInventory" _
& " SET Quantity = Quantity - @QuantityToTransfer" _
& " WHERE ProductID = @ProductID AND LocationID = @LocationID;"
reduceCommand.Parameters.Add("@ProductID", SqlDbType.Int)
reduceCommand.Parameters(0).Value = productID
reduceCommand.Parameters.Add("@LocationID", SqlDbType.SmallInt)
reduceCommand.Parameters(1).Value = fromLocationID
reduceCommand.Parameters.Add("@QuantityToTransfer", SqlDbType.SmallInt)
reduceCommand.Parameters(2).Value = quantityToTransfer
reduceCommand.ExecuteNonQuery()
'Increate inventory count at destination
Dim increaseCommand As SqlCommand = adventureworksConnection.CreateCommand()
increaseCommand.CommandText = "UPDATE Production.ProductInventory" _
& " SET Quantity = Quantity + @QuantityToTransfer" _
& " WHERE ProductID = @ProductID AND LocationID = @LocationID;"
increaseCommand.Parameters.Add("@ProductID", SqlDbType.Int)
increaseCommand.Parameters(0).Value = productID
increaseCommand.Parameters.Add("@LocationID", SqlDbType.SmallInt)
increaseCommand.Parameters(1).Value = toLocationID
increaseCommand.Parameters.Add("@QuantityToTransfer", SqlDbType.SmallInt)
increaseCommand.Parameters(2).Value = quantityToTransfer
increaseCommand.ExecuteNonQuery()
' Create an audit trail of the inventory transfer. We must impersonate the
' client credentials in order for this to work. Otherwise we'd have to
' set up security for the machine account.
'SqlConnection auditConnection = adventureworksConnection
Using auditConnection As New SqlConnection(auditConnectionString)
Dim auditCommand As SqlCommand = auditConnection.CreateCommand()
auditCommand.CommandText = "INSERT InventoryChange " _
& " (ProductID, FromLocationID, ToLocationID, Quantity) " _
& " VALUES (@ProductID, @FromLocationID, @ToLocationID, @Quantity);"
auditCommand.Parameters.Add("@ProductID", SqlDbType.Int)
auditCommand.Parameters(0).Value = productID
auditCommand.Parameters.Add("@FromLocationID", SqlDbType.SmallInt)
auditCommand.Parameters(1).Value = fromLocationID
auditCommand.Parameters.Add("@ToLocationID", SqlDbType.SmallInt)
auditCommand.Parameters(2).Value = toLocationID
auditCommand.Parameters.Add("@Quantity", SqlDbType.SmallInt)
auditCommand.Parameters(3).Value = quantityToTransfer
' Opening auditConnection automatically enlists it in the
' TransactionScope as part of the transaction.
auditConnection.Open()
auditCommand.ExecuteNonQuery()
End Using
End Using
' The Complete method commits the transaction.
transScope.Complete()
End Using
End Sub
End Class
这是 Transact-SQL 安装脚本 (Install.sql)，该脚本在数据库中部署程序集并创建存储过程。
USE AdventureWorks
GO
-- Drop existing sproc and assembly if any.
IF EXISTS (SELECT * FROM sys.procedures WHERE [name] = 'usp_ExecuteTransfer')
DROP PROCEDURE usp_ExecuteTransfer;
GO
IF EXISTS (SELECT * FROM sys.assemblies WHERE [name] = 'Transaction')
DROP ASSEMBLY [Transaction];
GO
USE master
GO
IF EXISTS (SELECT * FROM sys.server_principals WHERE [name] = 'ExternalSample_Login')
DROP LOGIN ExternalSample_Login;
GO
IF EXISTS (SELECT * FROM sys.asymmetric_keys WHERE [name] = 'ExternalSample_Key')
DROP ASYMMETRIC KEY ExternalSample_Key;
GO
DECLARE @SamplesPath nvarchar(1024)
-- You may need to modify the value of the this variable if you have installed the sample someplace other than the default location.
set @SamplesPath = 'C:\MySample\'
EXEC('CREATE ASYMMETRIC KEY ExternalSample_Key FROM EXECUTABLE FILE = ''' + @SamplesPath + 'Transaction.dll'';');
CREATE LOGIN ExternalSample_Login FROM ASYMMETRIC KEY ExternalSample_Key
GRANT EXTERNAL ACCESS ASSEMBLY TO ExternalSample_Login
GO
USE AdventureWorks
GO
DECLARE @SamplesPath nvarchar(1024)
-- You may need to modify the value of this variable if you have installed the sample someplace other than the default location.
set @SamplesPath = 'C:\MySample\'
-- Add the assembly and CLR integration based stored procedure
CREATE ASSEMBLY [Transaction]
FROM @SamplesPath + 'Transaction.dll'
WITH permission_set = External_Access;
GO
CREATE PROCEDURE usp_ExecuteTransfer
(
@ProductID int,
@FromLocationID smallint,
@ToLocationID smallint,
@QuantityToTransfer smallint
)
AS EXTERNAL NAME [Transaction].[InventoryMover].ExecuteTransfer;
GO
这是 Transact-SQL 安装脚本 (InstallDB.sql)，该脚本在第二个 SQL Server 实例中创建审核数据库。
SET NOCOUNT OFF;
GO
PRINT CONVERT(varchar(1000), @@VERSION);
GO
PRINT '';
PRINT 'Started - ' + CONVERT(varchar, GETDATE(), 121);
GO
USE [master];
GO
-- ****************************************
-- Drop Database
-- ****************************************
PRINT '';
PRINT '*** Dropping Database';
GO
IF EXISTS (SELECT [name] FROM [master].[sys].[databases] WHERE [name] = N'InventoryAudit')
DROP DATABASE [InventoryAudit];
-- If the database has any other open connections close the network connection.
IF @@ERROR = 3702
RAISERROR('[InventoryAudit] database cannot be dropped because there are still other open connections', 127, 127) WITH NOWAIT, LOG;
GO
-- ****************************************
-- Create Database
-- ****************************************
PRINT '';
PRINT '*** Creating Database';
GO
DECLARE
@sql_path nvarchar(256),
@sql_cmd nvarchar(256);
SELECT @sql_path = SUBSTRING([physical_name], 1, CHARINDEX(N'master.mdf', LOWER([physical_name])) - 1)
FROM [master].[sys].[master_files]
WHERE [database_id] = 1
AND [file_id] = 1;
-- COLLATE Latin1_General_CS_AS
EXECUTE (N'CREATE DATABASE [InventoryAudit]
ON (NAME = ''InventoryAudit_Data'', FILENAME = N''' + @sql_path + N'InventoryAudit_Data.mdf'', SIZE = 120, FILEGROWTH = 8)
LOG ON (NAME = ''InventoryAudit_Log'', FILENAME = N''' + @sql_path + N'InventoryAudit_Log.ldf'' , SIZE = 2, FILEGROWTH = 96);');
GO
ALTER DATABASE [InventoryAudit]
SET RECOVERY SIMPLE,
ANSI_NULLS ON,
ANSI_PADDING ON,
ANSI_WARNINGS ON,
ARITHABORT ON,
CONCAT_NULL_YIELDS_NULL ON,
QUOTED_IDENTIFIER ON,
NUMERIC_ROUNDABORT OFF,
PAGE_VERIFY CHECKSUM,
ALLOW_SNAPSHOT_ISOLATION OFF;
GO
USE [InventoryAudit];
GO
PRINT '';
PRINT '*** Creating Table';
GO
CREATE TABLE [InventoryChange] (
[InventoryChangeID] int IDENTITY (1, 1) NOT NULL,
[ProductID] int NOT NULL,
[FromLocationID] smallint,
[ToLocationID] smallint,
[Quantity] smallint NOT NULL
);
GO
这是 test.sql，该脚本通过执行函数测试该示例。
USE AdventureWorks
GO
SELECT 'Before first transfer quantity of adjustable races at Tool Crib = ', Quantity FROM Production.ProductInventory
WHERE ProductID = 1 AND LocationID = 1
SELECT 'Before first transfer quantity of adjustable races at Miscellaneous Storage = ', Quantity FROM Production.ProductInventory
WHERE ProductID = 1 AND LocationID = 6
--Move 12 adjustable race parts (product id 1) from the Tool Crib (location id 1)
--to Miscellaneous Storage (location id 6).
EXEC usp_ExecuteTransfer 1, 1, 6, 12
SELECT 'After first transfer quantity of adjustable races at Tool Crib = ', Quantity FROM Production.ProductInventory
WHERE ProductID = 1 AND LocationID = 1
SELECT 'After first transfer quantity of adjustable races at Miscellaneous Storage = ', Quantity FROM Production.ProductInventory
WHERE ProductID = 1 AND LocationID = 6
--Move them back
EXEC usp_ExecuteTransfer 1, 6, 1, 12
SELECT 'After second transfer quantity of adjustable races at Tool Crib = ', Quantity FROM Production.ProductInventory
WHERE ProductID = 1 AND LocationID = 1
SELECT 'After second transfer quantity of adjustable races at Miscellaneous Storage = ', Quantity FROM Production.ProductInventory
WHERE ProductID = 1 AND LocationID = 6
The following tsql removes the assembly and stored procedure from the database (Cleanup.sql).
USE AdventureWorks
GO
-- Drop existing sproc and assembly if any.
IF EXISTS (SELECT * FROM sys.procedures WHERE [name] = 'usp_ExecuteTransfer')
DROP PROCEDURE usp_ExecuteTransfer;
GO
IF EXISTS (SELECT * FROM sys.assemblies WHERE [name] = 'Transaction')
DROP ASSEMBLY [Transaction];
GO
USE master
GO
IF EXISTS (SELECT * FROM sys.server_principals WHERE [name] = 'ExternalSample_Login')
DROP LOGIN ExternalSample_Login;
GO
IF EXISTS (SELECT * FROM sys.asymmetric_keys WHERE [name] = 'ExternalSample_Key')
DROP ASYMMETRIC KEY ExternalSample_Key;
GO
USE AdventureWorks
GO
以下 Transact-SQL 从第二个实例中删除审核数据库。
SET NOCOUNT OFF;
GO
PRINT CONVERT(varchar(1000), @@VERSION);
GO
PRINT '';
PRINT 'Started - ' + CONVERT(varchar, GETDATE(), 121);
GO
USE [master];
GO
-- ****************************************
-- Drop Database
-- ****************************************
PRINT '';
PRINT '*** Dropping Database';
GO
IF EXISTS (SELECT [name] FROM [master].[sys].[databases] WHERE [name] = N'InventoryAudit')
DROP DATABASE [InventoryAudit];
-- If the database has any other open connections close the network connection.
IF @@ERROR = 3702
RAISERROR('[InventoryAudit] database cannot be dropped because there are still other open connections', 127, 127) WITH NOWAIT, LOG;
GO
下面的 Transact-SQL 从数据库中删除程序集和函数。
SE AdventureWorks
GO
-- Drop existing sproc and assembly if any.
IF EXISTS (SELECT * FROM sys.procedures WHERE [name] = 'usp_ExecuteTransfer')
DROP PROCEDURE usp_ExecuteTransfer;
GO
IF EXISTS (SELECT * FROM sys.assemblies WHERE [name] = 'Transaction')
DROP ASSEMBLY [Transaction];
GO
USE master
GO
IF EXISTS (SELECT * FROM sys.server_principals WHERE [name] = 'ExternalSample_Login')
DROP LOGIN ExternalSample_Login;
GO
IF EXISTS (SELECT * FROM sys.asymmetric_keys WHERE [name] = 'ExternalSample_Key')
DROP ASYMMETRIC KEY ExternalSample_Key;
GO
USE AdventureWorks
GO