Exemple de transactions CLR
Cet exemple montre comment contrôler les transactions à l'aide des API managées situées dans l'espace de noms System.Transactions. La classe System.Transactions.TransactionScope est notamment utilisée pour établir la limite d'une transaction de sorte que les chiffres de stock ne soient pas modifiés tant que le stock n'est pas suffisant pour répondre à la demande et, si le stock est suffisant, que le transfert du stock d'un emplacement à un autre s'effectue de manière atomique. L'inscription automatique dans une transaction distribuée s'effectue en enregistrant les modifications apportées au stock dans une base de données d'audit stockée sur une instance distincte de SQL Server.
Configuration préalable requise
Pour créer et exécuter ce projet, les logiciels suivants doivent être installés :
SQL Server ou SQL Server Express. Vous pouvez vous procurer gratuitement SQL Server Express à partir du site Web SQL Server Express Documentation and Samples (en anglais)
Base de données AdventureWorks qui est disponible sur le site Web du Centre pour les développeurs SQL Server
Le Kit de développement logiciel .NET Framework SDK 2.0 ou version ultérieure, ou Microsoft Visual Studio 2005 ou version ultérieure. Vous pouvez vous procurer gratuitement le Kit de développement logiciel .NET Framework SDK.
De plus, les conditions suivantes doivent être réunies :
L'intégration du CLR doit être activée sur l'instance SQL Server que vous utilisez.
Pour activer l'intégration du CLR, effectuez les étapes suivantes :
Activation de l'intégration du CLR
- Exécutez les commandes Transact-SQL suivantes :
sp_configure 'clr enabled', 1
GO
RECONFIGURE
GO
[!REMARQUE]
Pour activer l'intégration du CLR, vous devez disposer de l'autorisation de niveau serveur ALTER SETTINGS qui est attribuée implicitement aux membres des rôles serveur fixes sysadmin et serveradmin.
La base de données AdventureWorks doit être installée sur l'instance SQL Server que vous utilisez.
Si vous n'êtes pas administrateur de l'instance SQL Server utilisée, vous devez demander à un administrateur de vous accorder l'autorisation CreateAssembly pour terminer l'installation.
Génération de l'exemple
Créez et exécutez l'exemple à l'aide des instructions suivantes :
Ouvrez une invite de commandes Visual Studio ou .NET Framework.
Si nécessaire, créez un répertoire pour votre exemple. Pour cet exemple, nous utiliserons C:\MySample.
Puisque cet exemple requiert un assembly signé, créez une clé asymétrique en tapant la commande :
sn -k SampleKey.snk
Compilez l'exemple de code à partir de l'invite de ligne de commande en exécutant l'un des éléments suivants, selon le langage choisi.
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
Copiez le code de l'installation Transact-SQL dans un fichier et enregistrez-le sous install.sql dans le répertoire d'exemple.
Déployez l'assembly et la procédure stockée en exécutant
- sqlcmd -E -I -i install.sql -v root = "C:\MySample\"
Copiez le code de l'installation de base de données Transact-SQL dans un fichier et enregistrez-le sous installDB.sql dans le répertoire d'exemple.
Installez la base de données d'audit en exécutant
- Sqlcmd –S server_name [ \instance_name ] -E -I -i installDB.sql
avec les valeurs appropriées de l'instance et du serveur.
Copiez le script de la commande de test Transact-SQL dans un fichier et enregistrez-le sous test.sql dans le répertoire d'exemple.
Exécutez le script de test avec la commande suivante
- sqlcmd -E -I -i test.sql
Copiez le script de nettoyage de base de données Transact-SQL dans un fichier et enregistrez-la en tant que cleanupDB.sql dans le répertoire d'exemple.
Exécutez le script avec la commande suivante
Sqlcmd –S server_name [ \instance_name ] -E -I -i cleanup.sql
avec les valeurs appropriées de l'instance et du serveur.
Copiez le script de nettoyage Transact-SQL dans un fichier et enregistrez-le sous cleanup.sql dans le répertoire d'exemple.
Exécutez le script avec la commande suivante
- sqlcmd -E -I -i cleanup.sql
Exemple de code
Voici les listes de code pour cet exemple.
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
Il s'agit du script d'installation Transact-SQL (Install.sql), qui déploie l'assembly et crée la procédure stockée dans la base de données.
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
Il s'agit du script d'installation Transact-SQL (InstallDB.sql), qui crée la base de données d'audit dans la deuxième instance de SQL Server.
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
Il s'agit de test.sql, qui teste l'exemple en exécutant les fonctions.
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
Le code Transact-SQL suivant supprime la base de données d'audit de la deuxième instance
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
Le code Transact-SQL suivant supprime l'assembly et les fonctions de la base de données.
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
Voir aussi
Concepts
Scénarios et exemples d'utilisation pour l'intégration du CLR (Common Language Runtime)