Insert ข้อมูลแล้วไม่เข้าไปในฐานข้อมูล Windows CE ด้วย VB 2008

Dim conStr As String = "Data Source=" & _
            Path.GetDirectoryName(Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase) & _
            "\\AppDatabase.sdf"
        Dim con As SqlCeConnection = New SqlCeConnection(conStr)
        If con.State = ConnectionState.Closed Then con.Open()
        Dim sql As String
        sql = "insert into table1(id,des)values('" & TextBox1.Text.ToString & "','" & TextBox2.Text.ToString & "')"
        cmd = New SqlCeCommand(sql, con)
        cmd.ExecuteNonQuery()
        If myDS IsNot Nothing Then
            myDS.Clear()
        End If
        cmd = New SqlCeCommand("SELECT * FROM table1", con)
        If con.State = ConnectionState.Closed Then con.Open()
        myDA = New SqlCeDataAdapter(cmd)
        myDS = New DataSet()
        myDA.Fill(myDS, "tblProduct")
        DataGrid1.DataSource = myDS.Tables("tblProduct").DefaultView