Очистка неиспользуемой сборки

Пример AssemblyCleanup содержит хранимую процедуру .NET, которая очищает неиспользуемые сборки в текущей базе данных, запрашивая каталоги метаданных. Его единственный параметр используется для указания того, visible_assembliesследует ли удалять неиспользуемые видимые сборки. Значение false означает, что по умолчанию будут удалены только неиспользуемые невидимые сборки, в противном случае все неиспользуемые сборки будут удалены. Набор неиспользуемых сборок — это те сборки, которые не имеют определенных точек входа (подпрограммы и типы и агрегаты) и не используются сборки, ссылающиеся на них напрямую или косвенно.

Предпосылки

Чтобы создать и запустить этот проект, необходимо установить следующее программное обеспечение:

• SQL Server или SQL Server Express. Вы можете бесплатно получить SQL Server Express на веб-сайте документации и примеров SQL Server Express.

• База данных AdventureWorks, доступная на веб-сайте разработчика SQL Server

• Пакет SDK для .NET Framework 2.0 или более поздней версии или Microsoft Visual Studio 2005 или более поздней версии. Пакет SDK для .NET Framework можно получить бесплатно.

• Кроме того, необходимо выполнить следующие условия:

• Экземпляр SQL Server, который вы используете, должен включать интеграцию CLR.

• Чтобы включить интеграцию СРЕДЫ CLR, выполните следующие действия.

  Включение интеграции со средой CLR

  • Выполните следующие команды Transact-SQL:

  sp_configure 'clr enabled', 1

  GO

  RECONFIGURE

  GO

  Замечание

  Чтобы включить среду CLR, необходимо иметь ALTER SETTINGS разрешение на уровне сервера, которое неявно удерживается членами sysadmin ролей сервера и serveradmin предопределенных ролей сервера.

• База данных AdventureWorks должна быть установлена на используемом экземпляре SQL Server.

• Если вы не являетесь администратором используемого экземпляра SQL Server, необходимо предоставить администратору разрешение CreateAssembly для завершения установки.

Создание примера

Создайте и запустите пример, выполнив следующие инструкции:

1. Откройте командную строку Visual Studio или .NET Framework.

2. При необходимости создайте каталог для примера. В этом примере мы будем использовать C:\MySample.

3. В c:\MySample создайте AssemblyCleanup.vb (для примера Visual Basic) или AssemblyCleanup.cs (для примера C#) и скопируйте соответствующий пример кода Visual Basic или C# (ниже) в файл.

4. Скомпилируйте пример кода из командной строки, выполнив одно из следующих действий в зависимости от выбранного языка.

   • 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.Transactions.dll,C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.Xml.dll /target:library AssemblyCleanup.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.XML.dll /target:library AssemblyCleanup.cs

5. Скопируйте код установки Transact-SQL в файл и сохраните его как Install.sql в примере каталога.

6. Если образец установлен в каталоге другой C:\MySample\, измените файл Install.sql , как указано, чтобы указать на это расположение.

7. Развертывание сборки и хранимой процедуры путем выполнения

   • sqlcmd -E -I -i install.sql

8. Скопируйте Transact-SQL тестовый скрипт команды в файл и сохраните его как test.sql в примере каталога.

9. Выполнение тестового скрипта с помощью следующей команды

   • sqlcmd -E -I -i test.sql

10. Скопируйте скрипт очистки Transact-SQL в файл и сохраните его как cleanup.sql в примере каталога.

11. Выполнение скрипта с помощью следующей команды

    • sqlcmd -E -I -i cleanup.sql

Пример кода

Ниже приведены описания кода для этого примера.

C#

using System;  
using System.Text;  
using System.Diagnostics;  
using System.Data.SqlClient;  
using System.Collections.Generic;  
using System.Globalization;  
using Microsoft.SqlServer.Server;  
  
    /// <summary>  
    /// Defines a CLR user defined function CleanupUnusedAssemblies that drops   
    /// all the invisible assemblies with no references.  
    /// </summary>  
    public sealed class AssemblyCleanup  
    {  
        private SqlTransaction transaction;  
  
        internal class AssemblySet  
        {  
            private Dictionary<int, object> m_dictionary;  
  
            /// <summary>  
            /// Initialize internal structures  
            /// </summary>  
            /// <returns></returns>  
            public AssemblySet()  
            {  
                m_dictionary = new Dictionary<int, object>();  
            }  
  
            /// <summary>  
            /// Adds an assembly id into the current AssemblySet if it is not   
            /// already part of it.  
            /// </summary>  
            /// <returns></returns>  
            public void Add(int assemblyId)  
            {  
                if (!m_dictionary.ContainsKey(assemblyId))  
                {  
                    m_dictionary.Add(assemblyId, null);  
                }  
            }  
  
            /// <summary>  
            /// Number of assembly ids stored in this instance  
            /// </summary>  
            /// <returns></returns>  
            public int Count  
            {  
                get  
                {  
                    return m_dictionary.Count;  
                }  
            }  
  
            /// <summary>  
            /// Returns the comma-separated list of assembly ids contained in this instance  
            /// </summary>  
            /// <returns>string value that represents a comma-separated list   
            /// of assembly ids</returns>  
            public string ToCommaSeparatedList()  
            {  
                StringBuilder sb = new StringBuilder();  
  
                if (m_dictionary.Count > 0)  
                {  
                    foreach (KeyValuePair<int, object> kv in m_dictionary)  
                    {  
                        sb.Append(kv.Key);  
                        sb.Append(",");  
                    }  
  
                    sb.Length--; // remove the trailing comma  
                }  
  
                return sb.ToString();  
            }  
        }  
  
        /// <summary>  
        /// Initializes an instance of AssemblyCleanup with a SqlTransaction  
        /// </summary>  
        /// <returns></returns>  
        private AssemblyCleanup(SqlTransaction transaction)  
        {  
            this.transaction = transaction;  
        }  
  
        /// <summary>  
        /// Helper function that creates a SqlCommand object as part of the current   
        /// transaction  
        /// </summary>  
        /// <returns></returns>  
        private SqlCommand CreateCommandInTransaction()  
        {  
            SqlCommand cmd = this.transaction.Connection.CreateCommand();  
  
            cmd.Transaction = this.transaction;  
  
            return cmd;  
        }  
  
        /// <summary>  
        /// Helper function that constructs an AssemblySet instance using the   
        /// first column of the resultset resulting from the query that was passed in.  
        /// </summary>  
        /// <param name="query"></param>  
        /// <returns></returns>  
        private AssemblySet GetAssemblySetFromQuery(string query)  
        {  
            SqlCommand cmd = CreateCommandInTransaction();  
  
            AssemblySet set = new AssemblySet();  
  
            cmd.CommandText = query;  
            using (SqlDataReader rd = cmd.ExecuteReader())  
            {  
                while (rd.Read())  
                {  
                    set.Add(rd.GetInt32(0));  
                }  
            }  
  
            return set;  
        }  
  
        /// <summary>  
        /// Constructs a DROP ASSEMBLY T-SQL statement using the AssemblySet   
        /// passed in as a parameter.  
        /// </summary>  
        /// <param name="set"></param>  
        /// <returns></returns>  
        private void DropAssemblies(AssemblySet unusedAssemblySet)  
        {  
            if (unusedAssemblySet.Count > 0)  
            {  
                StringBuilder assemblyNamesToDrop = new StringBuilder();  
  
                // Gather the list of assembly names we will drop later  
                SqlCommand cmd = CreateCommandInTransaction();  
  
                cmd.CommandText = String.Format(CultureInfo.InvariantCulture,  
                    "SELECT name FROM sys.assemblies WHERE assembly_id IN ({0});",  
                    unusedAssemblySet.ToCommaSeparatedList());  
                using (SqlDataReader rd = cmd.ExecuteReader())  
                {  
                    while (rd.Read())  
                    {  
                        assemblyNamesToDrop.Append("[");  
                        assemblyNamesToDrop.Append(rd.GetString(0));  
                        assemblyNamesToDrop.Append("],");  
                    }  
                }  
  
                // Remove trailing comma  
                assemblyNamesToDrop.Length--;  
  
                // Drop all assemblies at the same time  
                cmd.CommandText = String.Format(CultureInfo.InvariantCulture,  
                    "DROP ASSEMBLY {0}", assemblyNamesToDrop.ToString());  
                cmd.ExecuteNonQuery();  
            }  
        }  
  
        /// <summary>  
        /// Serves as the stored procedure entry point and drives the process   
        /// of expanding the "assemblies in use" set, negating it, and   
        /// dropping the results  
        /// </summary>  
        /// <param name="visibleAssemblies">If set to true, will also drop   
        /// unused visible assemblies. Otherwise, will only drop unused invisible   
        /// assemblies.</param>  
        /// <returns></returns>  
        [Microsoft.SqlServer.Server.SqlProcedure()]  
        public static void CleanupUnusedAssemblies(bool visibleAssemblies)  
        {  
            bool succeeded = false;  
            SqlConnection conn;  
            SqlTransaction transaction;  
            string sqlStatement;  
            AssemblySet assembliesToDrop;  
            AssemblyCleanup assemblyCleanup;  
  
            conn = new SqlConnection("context connection=true");  
            conn.Open();  
            transaction = conn.BeginTransaction();  
  
            try  
            {  
                // Create a set of assemblies in use by looking at   
                // the metadata of the current database  
                sqlStatement =  
                    "DECLARE @UsedAssembly TABLE (AssemblyID int NOT NULL); " +  
                    "DECLARE @RowCount int; " +  
                    "INSERT INTO @UsedAssembly " +  
                    "SELECT DISTINCT([assembly_id]) " +  
                    "FROM sys.assembly_modules " +  
                    "UNION " +  
                    "SELECT [assembly_id] " +  
                    "FROM sys.assembly_types; " +  
                    "SET @RowCount = @@ROWCOUNT; " +  
                    "WHILE @RowCount > 0 " +  
                    "BEGIN " +  
                    "INSERT INTO @UsedAssembly " +  
                    "SELECT [referenced_assembly_id] " +  
                    "FROM sys.assembly_references ar " +  
                    "INNER JOIN @UsedAssembly ua " +  
                    "ON ar.[assembly_id] = ua.AssemblyID " +  
                    "WHERE NOT EXISTS (SELECT * FROM @UsedAssembly WHERE AssemblyID = [referenced_assembly_id]) " +  
                    "SET @RowCount = @@ROWCOUNT; " +  
                    "END;";  
  
                if (visibleAssemblies)  
                {  
                    sqlStatement +=  
                        "SELECT assembly_id " +  
                        "FROM sys.assemblies " +  
                        "WHERE assembly_id NOT IN (SELECT AssemblyID FROM @UsedAssembly);";  
                }  
                else  
                {  
                    sqlStatement +=  
                        "SELECT assembly_id " +  
                        "FROM sys.assemblies " +  
                        "WHERE assembly_id NOT IN (SELECT AssemblyID FROM @UsedAssembly) " +  
                        "    AND is_visible = 0;";  
                }  
  
                // This marks the beginning of the transaction  
                assemblyCleanup = new AssemblyCleanup(transaction);  
  
                // Assemblies that are currently in use  
                assembliesToDrop  
                    = assemblyCleanup.GetAssemblySetFromQuery(sqlStatement);  
  
                assemblyCleanup.DropAssemblies(assembliesToDrop);  
  
                // Mark as succeeded  
                succeeded = true;  
            }  
            finally  
            {  
                // We must guarantee that we explicitly call either Commit()   
                // or Rollback() before we return.  
                if (succeeded)  
                {  
                    transaction.Commit();  
                }  
                else  
                {  
                    transaction.Rollback();  
                }  
                conn.Dispose();  
            }  
        }  
    }  
  

Visual Basic

Imports Microsoft.SqlServer.Server  
Imports Microsoft.VisualBasic  
Imports System  
Imports System.Collections  
Imports System.Collections.Generic  
Imports System.Data  
Imports System.Data.SqlClient  
Imports System.Diagnostics  
Imports System.Globalization  
Imports System.Text  
Imports System.Transactions  
Public NotInheritable Class AssemblyCleanup  
    Private transaction As SqlTransaction  
  
    Friend Class AssemblySet  
        Private m_dictionary As Dictionary(Of Integer, Object)  
  
        ''' <summary>  
        ''' Initialize internal structures  
        ''' </summary>  
        ''' <returns></returns>  
        Public Sub New()  
            m_dictionary = New Dictionary(Of Integer, Object)  
        End Sub  
  
        ''' <summary>  
        ''' Adds an assembly id into the current AssemblySet if it is not already part of it.  
        ''' </summary>  
        ''' <returns></returns>  
        Public Sub Add(ByVal assemblyId As Integer)  
            If Not m_dictionary.ContainsKey(assemblyId) Then  
                m_dictionary.Add(assemblyId, Nothing)  
            End If  
        End Sub  
  
        ''' <summary>  
        ''' Number of assembly ids stored in this instance  
        ''' </summary>  
        ''' <returns></returns>  
        Public ReadOnly Property Count() As Integer  
            Get  
                Return m_dictionary.Count  
            End Get  
        End Property  
  
        ''' <summary>  
        ''' Returns the comma-separated list of assembly ids contained in this instance  
        ''' </summary>  
        ''' <returns>string value that represents a comma-separated list of assembly ids</returns>  
        Public Function ToCommaSeparatedList() As String  
            Dim sb As New StringBuilder()  
  
            If m_dictionary.Count > 0 Then  
                For Each kv As KeyValuePair(Of Integer, Object) In m_dictionary  
                    If (True) Then  
                        sb.Append(kv.Key)  
                        sb.Append(",")  
                    End If  
                Next  
  
                sb.Length -= 1 ' remove the trailing comma  
            End If  
  
            Return sb.ToString()  
  
        End Function  
    End Class  
  
    ''' <summary>  
    ''' Initializes an instance of AssemblyCleanup with a SqlTransaction  
    ''' </summary>  
    ''' <returns></returns>  
    Private Sub New(ByVal trans As SqlTransaction)  
        Me.transaction = trans  
    End Sub  
  
    ''' <summary>  
    ''' Helper function that creates a SqlCommand object as part of the   
    ''' current transaction  
    ''' </summary>  
    ''' <returns></returns>  
    Private Function CreateCommandInTransaction() As SqlCommand  
        Dim cmd As SqlCommand = transaction.Connection.CreateCommand()  
  
        cmd.Transaction = Me.transaction  
  
        Return cmd  
    End Function  
  
    ''' <summary>  
    ''' Helper function that constructs an AssemblySet instance using the   
    ''' first column of the resultset resulting from the query that was passed in.  
    ''' </summary>  
    ''' <param name="query"></param>  
    ''' <returns></returns>  
    Private Function GetAssemblySetFromQuery(ByVal query As String) As AssemblySet  
        Dim cmd As SqlCommand = CreateCommandInTransaction()  
        Dim [set] As New AssemblySet()  
  
        cmd.CommandText = query  
        Dim rd As SqlDataReader = cmd.ExecuteReader()  
        Try  
            While rd.Read()  
                [set].Add(rd.GetInt32(0))  
            End While  
        Finally  
            rd.Dispose()  
        End Try  
  
        Return [set]  
    End Function  
  
    ''' <summary>  
    ''' Constructs a DROP ASSEMBLY T-SQL statement using the AssemblySet   
    ''' passed in as a parameter.  
    ''' </summary>  
    ''' <param name="set"></param>  
    ''' <returns></returns>  
    Private Sub DropAssemblies(ByVal unusedAssemblySet As AssemblySet)  
        If unusedAssemblySet.Count > 0 Then  
            Dim assemblyNamesToDrop As New StringBuilder()  
  
            ' Gather the list of assembly names we will drop later  
            Dim cmd As SqlCommand = CreateCommandInTransaction()  
  
            cmd.CommandText = String.Format(CultureInfo.InvariantCulture, _  
                "SELECT name FROM sys.assemblies WHERE assembly_id IN ({0});", _  
                unusedAssemblySet.ToCommaSeparatedList())  
            Dim rd As SqlDataReader = cmd.ExecuteReader()  
            Try  
                While rd.Read()  
                    assemblyNamesToDrop.Append("[")  
                    assemblyNamesToDrop.Append(rd.GetString(0))  
                    assemblyNamesToDrop.Append("],")  
                End While  
            Finally  
                rd.Dispose()  
            End Try  
  
            ' Remove trailing comma  
            assemblyNamesToDrop.Length -= 1  
  
            ' Drop all assemblies at the same time  
            cmd.CommandText = String.Format(CultureInfo.InvariantCulture, _  
                "DROP ASSEMBLY {0}", assemblyNamesToDrop.ToString())  
            cmd.ExecuteNonQuery()  
        End If  
    End Sub  
  
    ''' <summary>  
    ''' Serves as the stored procedure entry point and drives the process of   
    ''' expanding the "assemblies in use" set, negating it, and dropping   
    ''' the results.  
    ''' </summary>  
    ''' <param name="visibleAssemblies">If set to true, will also drop unused   
    ''' visible assemblies. Otherwise, will only drop unused invisible assemblies.</param>  
    ''' <returns></returns>  
    <Microsoft.SqlServer.Server.SqlProcedure()> _  
    Public Shared Sub CleanupUnusedAssemblies(ByVal visibleAssemblies As Boolean)  
  
        Dim succeeded As Boolean = False  
        Dim conn As SqlConnection  
        Dim transaction As SqlTransaction  
        Dim sqlStatement As String  
        Dim assembliesToDrop As AssemblySet  
        Dim assemblyCleanup As AssemblyCleanup  
  
        conn = New SqlConnection("context connection=true")  
        conn.Open()  
        transaction = conn.BeginTransaction()  
  
        Try  
            ' Create a set of assemblies in use by looking at   
            ' the metadata of the current database  
            sqlStatement = "DECLARE @UsedAssembly TABLE (AssemblyID int NOT NULL); " & _  
                "DECLARE @RowCount int; " & _  
                "INSERT INTO @UsedAssembly " & _  
                "SELECT DISTINCT([assembly_id]) " & _  
                "FROM sys.assembly_modules " & _  
                "UNION " & _  
                "SELECT [assembly_id] " & _  
                "FROM sys.assembly_types; " & _  
                "SET @RowCount = @@ROWCOUNT; " & _  
                "WHILE @RowCount > 0 " & _  
                "BEGIN " & _  
                "INSERT INTO @UsedAssembly " & _  
                "SELECT [referenced_assembly_id] " & _  
                "FROM sys.assembly_references ar " & _  
                "INNER JOIN @UsedAssembly ua " & _  
                "ON ar.[assembly_id] = ua.AssemblyID " & _  
                "WHERE NOT EXISTS (SELECT * FROM @UsedAssembly WHERE AssemblyID = [referenced_assembly_id]) " & _  
                "SET @RowCount = @@ROWCOUNT; " & _  
                "END;"  
  
            If visibleAssemblies Then  
                sqlStatement += "SELECT assembly_id " & _  
                    "FROM sys.assemblies " & _  
                    "WHERE assembly_id NOT IN (SELECT AssemblyID FROM @UsedAssembly);"  
            Else  
                sqlStatement += "SELECT assembly_id " & _  
                    "FROM sys.assemblies " & _  
                    "WHERE assembly_id NOT IN (SELECT AssemblyID FROM @UsedAssembly) " & _  
                    "    AND is_visible = 0;"  
            End If  
  
            ' This marks the beginning of the transaction  
            assemblyCleanup = New AssemblyCleanup(transaction)  
  
            ' Assemblies that are currently in use  
            assembliesToDrop _  
                = assemblyCleanup.GetAssemblySetFromQuery(sqlStatement)  
  
            assemblyCleanup.DropAssemblies(assembliesToDrop)  
  
            ' Mark as succeeded  
            succeeded = True  
        Finally  
            ' We must guarantee that we explicitly call either Commit()   
            ' or Rollback() before we return.  
            If succeeded Then  
                transaction.Commit()  
            Else  
                transaction.Rollback()  
            End If  
            conn.Dispose()  
        End Try  
    End Sub  
End Class  

Это скрипт установки Transact-SQL (Install.sql), который развертывает сборку и создает хранимую процедуру в базе данных.

USE AdventureWorks;  
GO  
IF EXISTS (SELECT * FROM sys.objects WHERE name = N'CleanupUnusedAssemblies')  
DROP PROCEDURE CleanupUnusedAssemblies;  
GO  
  
IF EXISTS (SELECT * FROM sys.assemblies WHERE name = N'AssemblyCleanupUtils')   
DROP ASSEMBLY AssemblyCleanupUtils;  
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\'  
  
CREATE ASSEMBLY AssemblyCleanupUtils   
FROM @SamplesPath + 'AssemblyCleanup.dll'   
WITH permission_set = Safe;  
GO  
  
CREATE PROCEDURE CleanupUnusedAssemblies (  
@visible_assemblies bit  
) AS  
EXTERNAL NAME [AssemblyCleanupUtils].[AssemblyCleanup].CleanupUnusedAssemblies;  
GO  

Это , test.sqlкоторый проверяет пример, выполнив хранимую процедуру.

USE AdventureWorks;  
GO  
  
PRINT 'Before cleanup...'  
SELECT [name] FROM sys.assemblies;  
GO  
  
-- pass in false, which means the cleanup will only include invisible assemblies  
EXEC dbo.CleanupUnusedAssemblies false;  
GO  
  
PRINT 'After cleanup'  
SELECT [name] FROM sys.assemblies;  

Следующая Transact-SQL удаляет сборку и хранимую процедуру из базы данных.

USE AdventureWorks;  
GO  
  
IF EXISTS (SELECT * FROM sys.objects WHERE name = N'CleanupUnusedAssemblies')  
DROP PROCEDURE CleanupUnusedAssemblies;  
GO  
  
IF EXISTS (SELECT * FROM sys.assemblies WHERE name = N'AssemblyCleanupUtils')   
DROP ASSEMBLY AssemblyCleanupUtils;  
GO  

См. также

Сценарии использования и примеры интеграции со средой CLR