[RESOLVED] why recordcount returns -1?

[abdbuet]

Why I get recordcount=-1 in the following program?

Call connectionOpen
    Dim rs As ADODB.Recordset
    Set rs = New ADODB.Recordset
    Dim strSQL As String
    strSQL = "SELECT * FROM daily_list_cell WHERE show='Yes'"
    rs.Open strSQL,connection
    MsgBox rs.RecordCount
    rs.Close
    Set rs = Nothing
    Call connectionClose