SQL Server 提供程序统计信息 (ADO.NET)

更新：November 2007

从 .NET Framework 2.0 版开始，适用于 SQL Server 的 .NET Framework 数据提供程序支持运行时统计信息。必须在创建了有效的连接对象后将 SqlConnection 对象的 StatisticsEnabled 属性设置为 True，以启用统计信息。启用了统计信息之后，可以通过 SqlConnection 对象的 RetrieveStatistics 方法检索 IDictionary 引用，以将统计信息作为“实时快照”查看。通过列表作为一组名称/值对字典条目进行枚举。这些名称/值对不排序。可以随时调用 SqlConnection 对象的 ResetStatistics 方法，以重置计数器。如果尚未启用统计信息收集功能，则不会生成异常。此外，如果调用 RetrieveStatistics 之前没有先调用 StatisticsEnabled，检索到的值是每个条目的初始值。如果启用了统计信息，运行应用程序一段时间，然后禁用统计信息，检索到的值将反映在禁用统计信息之前收集的值。所有统计信息值按照连接进行收集。

可用的统计信息值

当前，Microsoft SQL Server 提供程序中共有 18 个不同的可用项。可用的项数可以通过 RetrieveStatistics 返回的 IDictionary 接口引用的 Count 属性进行访问。提供程序统计信息的所有计数器均使用公共语言运行库 Int64 类型（C# 和 Visual Basic 中为 long），宽度为 64 位。int64 数据类型的最大值由 int64.MaxValue 字段定义，最大值为 ((2^63)-1))。计数器的值达到此最大值时，应不再将这些值作为准确的值。这意味着 int64.MaxValue-1((2^63)-2) 实际上是任何统计信息的最大有效值。

说明：
字典用于返回提供程序统计信息，因为以后可能会更改返回的统计信息的数目、名称和顺序。应用程序不应依靠字典中找到的特定值，而应检查该值是否存在并相应进行分支。

下表说明当前可用的统计信息值。注意，在 Microsoft .NET Framework 的地区版本中，各个值的键名未本地化。

检索值

以下控制台应用程序显示如何在连接上启用统计信息，如何分别检索四个统计信息值，以及如何将统计信息输出到控制台窗口。

说明：
以下示例使用随 SQL Server 2005 提供的示例 AdventureWorks 数据库。示例代码中提供的连接字符串假定数据库在本地计算机上已安装并且可用。根据环境的需要修改连接字符串。

Option Strict On

Imports System
Imports System.Collections
Imports System.Data
Imports System.Data.SqlClient

Module Module1

  Sub Main()
    Dim connectionString As String = GetConnectionString()
    
    Using awConnection As New SqlConnection(connectionString)
      ' StatisticsEnabled is False by default.
      ' It must be set to True to start the 
      ' statistic collection process.
      awConnection.StatisticsEnabled = True

      Dim productSQL As String = "SELECT * FROM Production.Product"
      Dim productAdapter As _
          New SqlDataAdapter(productSQL, awConnection)

      Dim awDataSet As New DataSet()

      awConnection.Open()

      productAdapter.Fill(awDataSet, "ProductTable")

      ' Retrieve the current statistics as
      ' a collection of values at this point
      ' and time.
      Dim currentStatistics As IDictionary = _
          awConnection.RetrieveStatistics()

      Console.WriteLine("Total Counters: " & _
          currentStatistics.Count.ToString())
      Console.WriteLine()

      ' Retrieve a few individual values
      ' related to the previous command.
      Dim bytesReceived As Long = _
          CLng(currentStatistics.Item("BytesReceived"))
      Dim bytesSent As Long = _
          CLng(currentStatistics.Item("BytesSent"))
      Dim selectCount As Long = _
          CLng(currentStatistics.Item("SelectCount"))
      Dim selectRows As Long = _
          CLng(currentStatistics.Item("SelectRows"))

      Console.WriteLine("BytesReceived: " & bytesReceived.ToString())
      Console.WriteLine("BytesSent: " & bytesSent.ToString())
      Console.WriteLine("SelectCount: " & selectCount.ToString())
      Console.WriteLine("SelectRows: " & selectRows.ToString())

      Console.WriteLine()
      Console.WriteLine("Press any key to continue")
      Console.ReadLine()
    End Using

  End Sub

  Function GetConnectionString() As String
    ' To avoid storing the connection string in your code,
    ' you can retrive it from a configuration file.
    Return "Data Source=localhost;Integrated Security=SSPI;" & _
      "Initial Catalog=AdventureWorks"
  End Function
End Module

[C#]

using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;

namespace CS_Stats_Console_GetValue
{
  class Program
  {
    static void Main(string[] args)
    {
      string connectionString = GetConnectionString();

      using (SqlConnection awConnection = 
        new SqlConnection(connectionString))
      {
        // StatisticsEnabled is False by default.
        // It must be set to True to start the 
        // statistic collection process.
        awConnection.StatisticsEnabled = true;

        string productSQL = "SELECT * FROM Production.Product";
        SqlDataAdapter productAdapter = 
          new SqlDataAdapter(productSQL, awConnection);

        DataSet awDataSet = new DataSet();

        awConnection.Open();

        productAdapter.Fill(awDataSet, "ProductTable");
        // Retrieve the current statistics as
        // a collection of values at this point
        // and time.
        IDictionary currentStatistics =
          awConnection.RetrieveStatistics();

        Console.WriteLine("Total Counters: " +
          currentStatistics.Count.ToString());
        Console.WriteLine();

        // Retrieve a few individual values
        // related to the previous command.
        long bytesReceived =
            (long) currentStatistics["BytesReceived"];
        long bytesSent =
            (long) currentStatistics["BytesSent"];
        long selectCount =
            (long) currentStatistics["SelectCount"];
        long selectRows =
            (long) currentStatistics["SelectRows"];

        Console.WriteLine("BytesReceived: " +
            bytesReceived.ToString());
        Console.WriteLine("BytesSent: " +
            bytesSent.ToString());
        Console.WriteLine("SelectCount: " +
            selectCount.ToString());
        Console.WriteLine("SelectRows: " +
            selectRows.ToString());

        Console.WriteLine();
        Console.WriteLine("Press any key to continue");
        Console.ReadLine();
      }

    }
    private static string GetConnectionString()
    {
      // To avoid storing the connection string in your code,
      // you can retrive it from a configuration file.
      return "Data Source=localhost;Integrated Security=SSPI;" + 
        "Initial Catalog=AdventureWorks";
    }
  }
}

检索所有值

以下控制台应用程序显示如何在连接上启用统计信息，如何使用枚举器检索所有可用统计信息值，以及如何将统计信息输出到控制台窗口。

说明：
以下示例使用随 SQL Server 2005 提供的示例 AdventureWorks 数据库。示例代码中提供的连接字符串假定数据库在本地计算机上已安装并且可用。根据环境的需要修改连接字符串。

Option Strict On

Imports System
Imports System.Collections
Imports System.Data
Imports System.Data.SqlClient

Module Module1
  Sub Main()
    Dim connectionString As String = GetConnectionString()

    Using awConnection As New SqlConnection(connectionString)
      ' StatisticsEnabled is False by default.
      ' It must be set to True to start the 
      ' statistic collection process.
      awConnection.StatisticsEnabled = True

      Dim productSQL As String = "SELECT * FROM Production.Product"
      Dim productAdapter As _
          New SqlDataAdapter(productSQL, awConnection)

      Dim awDataSet As New DataSet()

      awConnection.Open()

      productAdapter.Fill(awDataSet, "ProductTable")

      ' Retrieve the current statistics as
      ' a collection of values at this point
      ' and time.
      Dim currentStatistics As IDictionary = _
          awConnection.RetrieveStatistics()


      Console.WriteLine("Total Counters: " & _
          currentStatistics.Count.ToString())
      Console.WriteLine()

      Console.WriteLine("Key Name and Value")

      ' Note the entries are unsorted.
      For Each entry As DictionaryEntry In currentStatistics
        Console.WriteLine(entry.Key.ToString() & _
            ": " & entry.Value.ToString())
      Next

      Console.WriteLine()
      Console.WriteLine("Press any key to continue")
      Console.ReadLine()
    End Using

  End Sub

  Function GetConnectionString() As String
    ' To avoid storing the connection string in your code,
    ' you can retrive it from a configuration file.
    Return "Data Source=localhost;Integrated Security=SSPI;" & _
      "Initial Catalog=AdventureWorks"
  End Function
End Module

using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.SqlClient;

namespace CS_Stats_Console_GetAll
{
  class Program
  {
    static void Main(string[] args)
    {
      string connectionString = GetConnectionString();

      using (SqlConnection awConnection = 
        new SqlConnection(connectionString))
      {
        // StatisticsEnabled is False by default.
        // It must be set to True to start the 
        // statistic collection process.
        awConnection.StatisticsEnabled = true;

        string productSQL = "SELECT * FROM Production.Product";
        SqlDataAdapter productAdapter =
            new SqlDataAdapter(productSQL, awConnection);

        DataSet awDataSet = new DataSet();

        awConnection.Open();

        productAdapter.Fill(awDataSet, "ProductTable");

        // Retrieve the current statistics as
        // a collection of values at this point
        // and time.
        IDictionary currentStatistics =
            awConnection.RetrieveStatistics();

        Console.WriteLine("Total Counters: " +
            currentStatistics.Count.ToString());
        Console.WriteLine();

        Console.WriteLine("Key Name and Value");

        // Note the entries are unsorted.
        foreach (DictionaryEntry entry in currentStatistics)
        {
          Console.WriteLine(entry.Key.ToString() +
              ": " + entry.Value.ToString());
        }

        Console.WriteLine();
        Console.WriteLine("Press any key to continue");
        Console.ReadLine();
      }

    }
    private static string GetConnectionString()
    {
      // To avoid storing the connection string in your code,
      // you can retrive it from a configuration file.
      return "Data Source=localhost;Integrated Security=SSPI;" + 
        "Initial Catalog=AdventureWorks";
    }
  }
}

请参见

其他资源

SQL Server 和 ADO.NET