怎樣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