UPDATE Mysql Record From Within <A HREF...>

I have a .asp page that displays an HTML page: view_msg.asp

There is a link (anchor tag) on that page that when clicked, sends the user to another page. I would like to also execute a MySQL query when that link is clicked. The DB is already open and connected to the page. The current current tag looks like this:

<a href="view_messages.asp"><IMG SRC="example.gif"></a>

and the MySql command I want to send is:
UPDATE Messages SET `fromDisplay`="N" WHERE idMessage=" & idMsg "

In english: When someone clicks on the link I want to execute a MySQL command to set the field value to N... how do I do that?

I know this is a very rookie question - but I don't know enough about asp to know how to execute the command here the way I want. Do I have to turn the image/button into a <FORM> 'submit' button</FORM> and use a redirect? Or, would I use an ONLCKICK. What would the correct syntax be?