找错

找错
Dim mydb As DAO.Database
    Dim myws As DAO.Workspace
    Dim mysql As String
    Dim myrec As DAO.RecordsetTypeEnum
    Friend WithEvents btsearchbooks As System.Windows.Forms.Button
    Friend WithEvents TxtsearchNumbers As System.windows.forms.TextBox

    Dim de As DAO.DBEngine = New DAO.DBEngine
    Public Function openDb() As Short
        Dim dbstr As String
        dbstr = "c:\lib.mdb"
        myws = de.Workspaces(0)
        mydb = myws.OpenDatabase(dbstr, False, False)
        dbstr = "select * from tblstudents"
        myrec = mydb.OpenRecordset(dbstr, DAO.RecordsetTypeEnum.dbOpenDynaset)
    End Function

请问这一段有什么错误，谢谢