How to update one element in column chose with Select in VB.NET

Hi guys,

This is my first post and so glad to start sharing the knowledge.

I am using Mysql database with VB.NET and I have this code :

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        Dim str As String = "Server=localhost;Port=3306;Database=testdb;Uid=root;Pwd=password"

        Using con As New MySqlConnection(str)

            Dim query As String = "select * from testdata where rfid_tag='" & TextBox3.Text & "' and Date_serve<= '" & Date.Now.ToString("yyyy-MM-dd ") & "' and Start_Time<= '" & Date.Now.ToString("HH:mm:ss ") & "' and End_Time>= '" & Date.Now.ToString("HH:mm:ss ") & "' or amount_serve='' "
            Dim cm As New MySqlCommand(query, con)

            con.Open()

            Dim rd As MySqlDataReader = cm.ExecuteReader()

            ' Check if any rows exist
            If rd.Read() Then
                If rd.GetString(3) = "small" Then

                    MessageBox.Show("small")

                ElseIf rd.GetString(3) = "Big" Then

                    MessageBox.Show("big")

                ElseIf rd.GetString(3) = "Midium" Then

                    MessageBox.Show("Mid")

                End If

            End If
        End Using

    End Sub

what I want after take action after any of If function like

If rd.GetString(3) = "small" Then

                        MessageBox.Show("small")

need to update End_Time to be 00:00:00 in the element which chose in select with rfid_tag number in the table.

this my database table: for example if in "select" command choose RFID_TAG for John then I need to update the End_Time in table to be 00:00:00 with "update" command!

How can I achieve this?

  ID   First_Name      Date_Serve     Start_Time      End_Time             RFID_Tag           Amount_Serve
---------------------------------------------------------------------------------------------------------------------------------
    1     John           17-11-2018       10:00:00      10:15:00          hdgdYun8JH      Small
    2     George         18-11-2018      11:00:00       11:15:00           kdjfHluhHB        Big

Thanks for all

Javascript file is not triggering the function

I am using Netbean IDE 8.1 to build the website.
I build a very simple website with simple Javascript function, window.alert().
Upon my testing, I put the button triggered function in the javascript but the function is not triggering.
If I put the function under the HTML, it does triggered the function.
Any idea?

Please note that I also have linked my HTML file to the Javascript file.