如何確定有多少人登陸數(shù)據(jù)庫？

Sub ShowUserRosterMultipleUsers()
     Dim cn As New ADODB.Connection
     Dim cn2 As New ADODB.Connection
     Dim rs As New ADODB.Recordset
     Dim i, j As Long
     cn.Provider = "Microsoft.Jet.OLEDB.4.0"
     cn.Open "Data Source=c:\Northwind.mdb"
     cn2.Open "Provider=Microsoft.Jet.OLEDB.4.0;" _
     & "Data Source=c:\Northwind.mdb"
     ' The user roster is exposed as a provider-specific schema rowset
     ' in the Jet 4 OLE DB provider. You have to use a GUID to
     ' reference the schema, as provider-specific schemas are not
     ' listed in ADO's type library for schema rowsets
     Set rs = cn.OpenSchema(adSchemaProviderSpecific, _
     , "{947bb102-5d43-11d1-bdbf-00c04fb92675}")
     'Output the list of all users in the current database.
     Debug.Print rs.Fields(0).Name, "", rs.Fields(1).Name, _
     "", rs.Fields(2).Name, rs.Fields(3).Name
     While Not rs.EOF
     Debug.Print rs.Fields(0), rs.Fields(1), _
     rs.Fields(2), rs.Fields(3)
     rs.MoveNext
     Wend
    End Sub