Dim Connessione As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=|DataDirectory|\dbATTI.mdb")

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

        Connessione.Open()

        Dim numero_atto As Integer = 15536

        If Connessione.State = ConnectionState.Open Then

            MessageBox.Show(numero_atto) ' mi serve per capire quanto vale la variabile

            Dim MioCodiceSql As String = "SELECT * FROM preg_atti WHERE numero =" & numero_atto

            Dim MioCommand As New OleDbCommand(MioCodiceSql, Connessione)

            Dim reader As OleDbDataReader = MioCommand.ExecuteReader()
            While reader.Read()
                MsgBox(reader(0).ToString() & " - Numero: " & reader(1).ToString() & " - Data: " & reader(2).ToString())
            End While
            reader.Close()

        End If

        Connessione.Close()

    End Sub