[SqlClientPermission(SecurityAction.Demand, Unrestricted=true)]
public class SqlSiteMapProvider : StaticSiteMapProvider
{
    ... // static error messages omitted

    const string _cacheDependencyName = "__SiteMapCacheDependency";

    private string _connect;
    private string _database, _table;
    private bool _2005dependency = false;
    private int _indexID, _indexTitle, _indexUrl, _indexDesc,
        indexRoles, _indexParent;
    private Dictionary<int, SiteMapNode> _nodes =
        new Dictionary<int, SiteMapNode>(16);
    private SiteMapNode _root;
    private readonly object _lock = new object();

    public override void Initialize (
        string name, NameValueCollection config)
    {
        // Verify parameters
        if (config == null) throw new ArgumentNullException("config");
        if (String.IsNullOrEmpty(name)) name = "SqlSiteMapProvider";

        // Add a default "description" attribute to config if the
        // attribute doesn't exist or is empty
        if (string.IsNullOrEmpty(config["description"]))
        {
            config.Remove("description");
            config.Add("description", "SQL site map provider");
        }

        // Call the base class's Initialize method
        base.Initialize(name, config);

        // Initialize _connect
        string connect = config["connectionStringName"];
        if (String.IsNullOrEmpty(connect))
            throw new ProviderException(_errmsg5);
        config.Remove("connectionStringName");

        if (WebConfigurationManager.ConnectionStrings[connect] == null)
            throw new ProviderException(_errmsg6);
        _connect = WebConfigurationManager.ConnectionStrings[
            connect].ConnectionString;
        if (String.IsNullOrEmpty(_connect))
            throw new ProviderException(_errmsg7);
        
        // Initialize SQL cache dependency info
        string dependency = config["sqlCacheDependency"];

        if (!String.IsNullOrEmpty(dependency))
        {
            if (String.Equals(dependency, "CommandNotification",
                StringComparison.InvariantCultureIgnoreCase))
            {
                SqlDependency.Start(_connect);
                _2005dependency = true;
            }
            else
            {
                // If not "CommandNotification", then extract
                // database and table names
                string[] info = dependency.Split(new char[] { ':' });
                if (info.Length != 2)
                    throw new ProviderException(_errmsg8);
                _database = info[0];
                _table = info[1];
            }

            config.Remove("sqlCacheDependency");
        }
        
        // Throw an exception if unrecognized attributes remain
        if (config.Count > 0)
        {
            string attr = config.GetKey(0);
            if (!String.IsNullOrEmpty(attr))
                throw new ProviderException(
                    "Unrecognized attribute: " + attr);
        }
    }

    public override SiteMapNode BuildSiteMap()
    {
        lock (_lock)
        {
            // Return immediately if this method has been called before
            if (_root != null) return _root;

            // Query the database for site map nodes
            using(SqlConnection connection = new SqlConnection(_connect))
            {
                SqlCommand command = new SqlCommand(
                    "proc_GetSiteMap", connection);
                command.CommandType = CommandType.StoredProcedure;

                // Create a SQL cache dependency if requested
                SqlCacheDependency dependency = null;
                if (_2005dependency)
                    dependency = new SqlCacheDependency(command);
                else if (!String.IsNullOrEmpty(_database) &&
                         !String.IsNullOrEmpty(_table))
                    dependency = new SqlCacheDependency(_database,
                        _table);

                connection.Open();
                SqlDataReader reader = command.ExecuteReader();
                _indexID = reader.GetOrdinal("ID");
                _indexUrl = reader.GetOrdinal("Url");
                _indexTitle = reader.GetOrdinal("Title");
                _indexDesc = reader.GetOrdinal("Description");
                _indexRoles = reader.GetOrdinal("Roles");
                _indexParent = reader.GetOrdinal("Parent");

                if (reader.Read())
                {
                    // Create the root SiteMapNode and add it to site map
                    _root = CreateSiteMapNodeFromDataReader(reader);
                    AddNode(_root, null);

                    // Build a tree of SiteMapNodes under the root node
                    while (reader.Read())
                    {
                        // Create another site map node and add it 
                        AddNode(CreateSiteMapNodeFromDataReader(reader),
                            GetParentNodeFromDataReader(reader));
                    }

                    // Use the SQL cache dependency
                    if (dependency != null)
                    {
                        HttpRuntime.Cache.Insert(_cacheDependencyName,
                            new object(), dependency,
                            Cache.NoAbsoluteExpiration,
                            Cache.NoSlidingExpiration,
                            CacheItemPriority.NotRemovable,
                            new CacheItemRemovedCallback(
                              OnSiteMapChanged));
                    }
                }
            }

            // Return the root SiteMapNode
            return _root;
        }
    }

    protected override SiteMapNode GetRootNodeCore ()
    {
        return BuildSiteMap();
    }

    ... // Helper methods CreateSiteMapNodeFromDataReader and 
        // GetParentNodeFromDataReader
}

<configuration>
  <connectionStrings>
    <add name="SiteMapConnectionString"
      connectionString="..."
      providerName="System.Data.SqlClient" />
  </connectionStrings>
  <system.web>
    <siteMap enabled="true" defaultProvider="AspNetSqlSiteMapProvider">
      <providers>
        <add name="AspNetSqlSiteMapProvider"
          type="SqlSiteMapProvider"
          securityTrimmingEnabled="true"
          connectionStringName="SiteMapConnectionString"
          sqlCacheDependency="SiteMapDatabase:SiteMap" />
      </providers>
    </siteMap>
    <caching>
      <sqlCacheDependency enabled="true" pollTime="5000">
        <databases>
          <add name="SiteMapDatabase"
            connectionStringName="SiteMapConnectionString" />
        </databases>
      </sqlCacheDependency>
    </caching>
  </system.web>
</configuration>

<configuration>
  <connectionStrings>
    <add name="SiteMapConnectionString"
      connectionString="..."
      providerName="System.Data.SqlClient" />
  </connectionStrings>
  <system.web>
    <siteMap enabled="true" defaultProvider="AspNetSqlSiteMapProvider">
      <providers>
        <add name="AspNetSqlSiteMapProvider"
          type="SqlSiteMapProvider"
          securityTrimmingEnabled="true"
          connectionStringName="SiteMapConnectionString"
          sqlCacheDependency="CommandNotification" />
      </providers>
    </siteMap>
    <caching>
      <sqlCacheDependency enabled="true" />
    </caching>
  </system.web>
</configuration>

-- Create the site map node table

CREATE TABLE [dbo].[SiteMap] (
    [ID]          [int] NOT NULL,
    [Title]       [varchar] (32),
    [Description] [varchar] (512),
    [Url]         [varchar] (512),
    [Roles]       [varchar] (512),
    [Parent]      [int]
) ON [PRIMARY]
GO

ALTER TABLE [dbo].[SiteMap] ADD 
    CONSTRAINT [PK_SiteMap] PRIMARY KEY CLUSTERED 
    (
        [ID]
    )  ON [PRIMARY] 
GO

-- Add site map nodes

INSERT INTO SiteMap (ID, Title, Description, Url, Roles, Parent)
VALUES (1, 'Home', NULL, '~/Default.aspx', NULL, NULL)

INSERT INTO SiteMap (ID, Title, Description, Url, Roles, Parent)
VALUES (10, 'News', NULL, NULL, '*', 1)

INSERT INTO SiteMap (ID, Title, Description, Url, Roles, Parent)
VALUES (11, 'Local', 'News from greater Seattle', '~/Summary.aspx?CategoryID=0', NULL, 10)

INSERT INTO SiteMap (ID, Title, Description, Url, Roles, Parent)
VALUES (12, 'World', 'News from around the world', '~/Summary.aspx?CategoryID=2', NULL, 10)

INSERT INTO SiteMap (ID, Title, Description, Url, Roles, Parent)
VALUES (20, 'Sports', NULL, NULL, '*', 1)

INSERT INTO SiteMap (ID, Title, Description, Url, Roles, Parent)
VALUES (21, 'Baseball', 'What''s happening in baseball', '~/Summary.aspx?CategoryID=3', NULL, 20)

...

-- Create the stored proc used to query site map nodes

CREATE PROCEDURE proc_GetSiteMap AS
    SELECT [ID], [Title], [Description], [Url], [Roles], [Parent]
    FROM [SiteMap] ORDER BY [ID]
GO