如果你在SSMS内，你可能会发现它更容易使用:

SELECT @@Version

这里有一个简单的方法: 去 然后开始 程序然后 然后是SQL Server 2005 配置工具 然后是SQL Server配置管理器 然后进行SQL Server 2005网络配置 在这里，您可以找到安装到您的机器上的所有实例。

如果你在SSMS内，你可能会发现它更容易使用:

SELECT @@Version

SQL Server permits applications to find SQL Server instances within the current network. The SqlDataSourceEnumerator class exposes this information to the application developer, providing a DataTable containing information about all the visible servers. This returned table contains a list of server instances available on the network that matches the list provided when a user attempts to create a new connection, and expands the drop-down list containing all the available servers on the Connection Properties dialog box. The results displayed are not always complete. In order to retrieve the table containing information about the available SQL Server instances, you must first retrieve an enumerator, using the shared/static Instance property:

using System.Data.Sql;

class Program
{
  static void Main()
  {
    // Retrieve the enumerator instance and then the data.
    SqlDataSourceEnumerator instance =
      SqlDataSourceEnumerator.Instance;
    System.Data.DataTable table = instance.GetDataSources();

    // Display the contents of the table.
    DisplayData(table);

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

  private static void DisplayData(System.Data.DataTable table)
  {
    foreach (System.Data.DataRow row in table.Rows)
    {
      foreach (System.Data.DataColumn col in table.Columns)
      {
        Console.WriteLine("{0} = {1}", col.ColumnName, row[col]);
      }
      Console.WriteLine("============================");
    }
  }
}

来自MSDN http://msdn.microsoft.com/en-us/library/a6t1z9x2(v=vs.80).aspx

——T-SQL查询查找机器上已安装的实例列表

DECLARE @GetInstances TABLE
( Value nvarchar(100),
 InstanceNames nvarchar(100),
 Data nvarchar(100))

Insert into @GetInstances
EXECUTE xp_regread
  @rootkey = 'HKEY_LOCAL_MACHINE',
  @key = 'SOFTWARE\Microsoft\Microsoft SQL Server',
  @value_name = 'InstalledInstances'

Select InstanceNames from @GetInstances 

另一个选择是运行SQLSERVER发现报告，进入SQLSERVER安装介质，双击setup.exe

在下一个屏幕中，转到工具并单击如下所示的发现报告

这将向你展示所有的实例以及整个功能..下面是我电脑上的快照