同處理序資料存取範例
此 InProcessDataAccess 範例包含數個簡單函式，可示範 SQL Server CLR 進程資料存取提供者的各種功能。
必要條件
若要建立並執行這個專案，您必須安裝下列軟體：
SQL Server或SQL Server Express。 您可以從SQL Server Express檔和範例網站免費取得SQL Server Express
SQL Server Developer網站上可用的 AdventureWorks 資料庫
.NET Framework SDK 2.0 或更新版本或是 Microsoft Visual Studio 2005 或更新版本。 您可以免費取得 .NET Framework SDK。
此外，您也必須符合下列條件：
您使用的SQL Server實例必須啟用 CLR 整合。
若要啟用 CLR 整合，請執行下列步驟：
啟用 CLR 整合
- 執行下列 Transact-SQL 命令：
sp_configure 'clr enabled', 1GORECONFIGUREGO注意
若要啟用 CLR 整合，您必須擁有
ALTER SETTINGS伺服器層級權限，此權限是由系統管理員 (sysadmin) 和伺服器管理員 (serveradmin) 固定伺服器角色的成員以隱含方式持有。AdventureWorks 資料庫必須安裝在您使用SQL Server實例上。
如果您不是您所使用SQL Server實例的系統管理員，您必須擁有系統管理員授與CreateAssembly許可權才能完成安裝。
建立範例
使用下列指示來建立並執行範例：
開啟 Visual Studio 或 .NET Framework 命令提示字元。
必要時，請建立範例的目錄。 在此範例中，我們將使用 C:\MySample。
在 c:\MySample 中，建立
inprocda.vb(適用於 Visual Basic 範例) 或inprocda.cs(適用於 C# 範例) 並將適當的 Visual Basic 或 C# 範例程式碼 (下面) 複製到檔案中。根據您選擇的語言，在命令列提示字元中執行下列其中一段程式碼，藉以將範例程式碼編譯成必要的組件。
Vbc /reference: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.Xml.dll /target:library InProcDA.vbCsc /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.XML.dll /target:library inprocda.cs
將 Transact-SQL 安裝程式碼複製到檔案中，並將它儲存為
Install.sql範例目錄中。如果此範例安裝在
C:\MySample\以外的目錄中，請依照指示編輯Install.sql檔案，以指向該位置。部署組件、預存程序和函數，方法是執行
sqlcmd -E -I -i install.sql
將 Transact-SQL 安裝程式碼複製到檔案中，並將它儲存為
test.sql範例目錄中。在命令提示字元中執行下列程式碼行，藉以測試應用程式：
sqlcmd -E -I -i test.sql
將 Transact-SQL 清除腳本複製到檔案中，並將它儲存為
cleanup.sql範例目錄中。使用下列命令來執行指令碼
sqlcmd -E -I -i cleanup.sql
範例程式碼
下面是此範例的程式碼清單。
C#
using System;
using System.Data;
using System.Data.Sql;
using System.Data.SqlTypes;
using System.Data.SqlClient;
using Microsoft.SqlServer.Server;
public sealed class DataAccessDemo
{
private DataAccessDemo()
{
}
/// <summary>
/// Simple example to send a message to the client.
/// </summary>
public static void SendMessage(string msg)
{
SqlContext.Pipe.Send("Message from server: " + msg);
}
/// <summary>
/// Simple example of performing data access within
/// a function
/// </summary>
/// <returns></returns>
[Microsoft.SqlServer.Server.SqlFunction(DataAccess = Microsoft.SqlServer.Server.DataAccessKind.Read)]
public static string ReportSqlVersion()
{
using (SqlConnection conn = new SqlConnection("context connection=true"))
{
//create a command from the current context
SqlCommand cmd = conn.CreateCommand();
//execute something
cmd.CommandText = "select @@version";
conn.Open();
//return results as scalar
return (string)cmd.ExecuteScalar();
}
}
/// <summary>
/// Create a result set on the fly and send it to the client.
/// </summary>
public static void SendTransientResultSet()
{
//create the metadata for the columns
Microsoft.SqlServer.Server.SqlMetaData[] columnSchema
= new Microsoft.SqlServer.Server.SqlMetaData[] {
new Microsoft.SqlServer.Server.SqlMetaData("stringcol", SqlDbType.NVarChar, 128)
};
//create a record based on that metadata
SqlDataRecord newRecord = new SqlDataRecord(columnSchema);
//populate it
newRecord.SetString(0, "Hello World!");
//send it
SqlContext.Pipe.Send(newRecord);
}
/// <summary>
/// Execute a command and send the results to the client directly.
/// </summary>
public static void ExecuteToClient()
{
using (SqlConnection conn = new SqlConnection("context connection=true"))
{
SqlCommand cmd = conn.CreateCommand();
cmd.CommandText = "select @@version";
conn.Open();
SqlContext.Pipe.ExecuteAndSend(cmd);
}
}
/// <summary>
/// Execute a command and send the resultig reader to the client
/// </summary>
public static void SendReaderToClient()
{
using (SqlConnection conn = new SqlConnection("context connection=true"))
{
SqlCommand cmd = conn.CreateCommand();
cmd.CommandText = "select @@version";
conn.Open();
SqlDataReader rdr = cmd.ExecuteReader();
try
{
SqlContext.Pipe.Send(rdr);
}
finally
{
rdr.Close();
}
}
}
};
Visual Basic
Imports Microsoft.SqlServer.Server
Imports Microsoft.VisualBasic
Imports System
Imports System.Collections
Imports System.Data
Imports System.Data.Sql
Imports System.Data.SqlClient
Imports System.Data.SqlTypes
Imports System.Diagnostics
Partial Public NotInheritable Class DataAccessDemo
Private Sub New()
End Sub
''' <summary>
''' Simple example of performing data access within a function
''' </summary>
''' <returns></returns>
<SqlFunction(DataAccess:=DataAccessKind.Read)> _
Public Shared Function ReportSqlVersion() As SqlString
Using conn As New SqlConnection("context connection=true")
'create a command from the current context
Dim cmd As SqlCommand = conn.CreateCommand()
'execute something
cmd.CommandText = "SELECT @@VERSION"
conn.Open()
'return results as scalar
Return CType(cmd.ExecuteScalar(), String)
End Using
End Function
''' <summary>
''' Simple example to send a message to the client.
''' </summary>
Public Shared Sub SendMessage(ByVal msg As String)
SqlContext.Pipe.Send(("Message from server: " & msg))
End Sub
''' <summary>
''' Create a result set on the fly and send it to the client.
''' </summary>
Public Shared Sub SendTransientResultSet()
'create the metadata for the columns
Dim columnSchema() As Microsoft.SqlServer.Server.SqlMetaData _
= {New SqlMetaData("stringcol", SqlDbType.NVarChar, 128)}
'create a record based on that metadata
Dim newRecord As New SqlDataRecord(columnSchema)
'populate it
newRecord.SetString(0, "Hello World!")
'send it
SqlContext.Pipe.Send(newRecord)
End Sub
''' <summary>
''' Execute a command and send the results to the client directly.
''' </summary>
Public Shared Sub ExecuteToClient()
Using conn As New SqlConnection("context connection=true")
Dim cmd As SqlCommand = conn.CreateCommand()
cmd.CommandText = "SELECT @@VERSION"
conn.Open()
SqlContext.Pipe.ExecuteAndSend(cmd)
End Using
End Sub
''' <summary>
''' Execute a command and send the resulting reader to the client
''' </summary>
Public Shared Sub SendReaderToClient()
Using conn As New SqlConnection("context connection=true")
Dim cmd As SqlCommand = conn.CreateCommand()
cmd.CommandText = "SELECT @@VERSION"
conn.Open()
Dim rdr As SqlDataReader = cmd.ExecuteReader()
Try
SqlContext.Pipe.Send(rdr)
Finally
rdr.Close()
End Try
End Using
End Sub
End Class
這是 () Install.sql 的 Transact-SQL 安裝腳本，它會部署元件，並建立此範例所需的預存程式和函式。
USE AdventureWorks;
GO
IF EXISTS (SELECT * FROM sys.procedures WHERE name = N'SendMessage')
DROP PROCEDURE SendMessage;
GO
IF EXISTS (SELECT * FROM sys.procedures WHERE name = N'SendTransientResultSet')
DROP PROCEDURE SendTransientResultSet;
GO
IF EXISTS (SELECT * FROM sys.procedures WHERE name = N'ExecuteToClient')
DROP PROCEDURE ExecuteToClient;
GO
IF EXISTS (SELECT * FROM sys.procedures WHERE name = N'SendReaderToClient')
DROP PROCEDURE SendReaderToClient;
GO
IF EXISTS (SELECT * FROM sys.objects WHERE name = N'ReportSqlVersion' and (type = 'FS' or type = 'FT'))
DROP FUNCTION [ReportSqlVersion];
GO
IF EXISTS (SELECT * FROM sys.assemblies WHERE name = N'InProcDA') DROP ASSEMBLY InProcDA;
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 = N'C:\MySample\'
CREATE ASSEMBLY InProcDA FROM @SamplesPath + 'InProcDA.dll'
WITH permission_set = SAFE;
GO
CREATE PROCEDURE [SendMessage] @msg nvarchar(4000)
AS
EXTERNAL NAME [InProcDA].[DataAccessDemo].[SendMessage];
GO
CREATE FUNCTION [ReportSqlVersion]() RETURNS nvarchar(4000)
AS EXTERNAL NAME [InProcDA].[DataAccessDemo].[ReportSqlVersion];
GO
CREATE PROCEDURE [SendTransientResultSet]
AS
EXTERNAL NAME [InProcDA].[DataAccessDemo].[SendTransientResultSet];
GO
CREATE PROCEDURE [ExecuteToClient]
AS
EXTERNAL NAME [InProcDA].[DataAccessDemo].[ExecuteToClient];
GO
CREATE PROCEDURE [SendReaderToClient]
AS
EXTERNAL NAME [InProcDA].[DataAccessDemo].[SendReaderToClient];
GO
下列 Transact-SQL (test.sql) 藉由執行此範例中定義的預存程式和函式來測試此範例。
USE AdventureWorks;
GO
-- send a message to the client
EXEC SendMessage N'This is a test message.';
-- exec a function that does data access
SELECT dbo.ReportSqlVersion();
-- exec the proc that sends a result set to the client
EXEC SendTransientResultSet;
EXEC ExecuteToClient;
EXEC SendReaderToClient;
USE master;
GO
下列 Transact-SQL 會從資料庫移除元件、函式和預存程式。
USE AdventureWorks
GO
IF EXISTS (SELECT * FROM sys.procedures WHERE name = N'SendMessage')
DROP PROCEDURE SendMessage;
GO
IF EXISTS (SELECT * FROM sys.procedures WHERE name = N'SendTransientResultSet')
DROP PROCEDURE SendTransientResultSet;
GO
IF EXISTS (SELECT * FROM sys.procedures WHERE name = N'ExecuteToClient')
DROP PROCEDURE ExecuteToClient;
GO
IF EXISTS (SELECT * FROM sys.procedures WHERE name = N'SendReaderToClient')
DROP PROCEDURE SendReaderToClient;
GO
IF EXISTS (SELECT * FROM sys.objects WHERE name = N'ReportSqlVersion' and (type = 'FS' or type = 'FT'))
DROP FUNCTION [ReportSqlVersion];
GO
IF EXISTS (SELECT * FROM sys.assemblies WHERE name = N'InProcDA') DROP ASSEMBLY InProcDA;
GO