A simple HTML form that uses AJAX/PHP to access MySQL

I have a MySQL database which I access though PHP. I want to create a dynamic webpage where if a certain field in the MySQL data contains a value (say "ON" instead of "OFF"), then the webpage displays an HTML form. I only want the HTML form to display if the value in the database is "ON" instead of "OFF". It needs to automatically disappear if the value in the MySQL database changes to "OFF". It's fine if this check/refresh (AJAX?) happens every five seconds or so - but it can't make the form hard to use (i.e. I don't want the whole page refreshing every five seconds so that someone can't actually fill in and submit the form). The form itself needs to be dynamically generated from PHP/MySQL queries, so I'm thinking an AJAX call that displays the outputs of a PHP script would be fine. However, I don't know how to do the AJAX/JavaScript display stuff. Here's what I need you to give me: 1. A simple HTML page containing an appropriate AJAX script that would do what I've said above, returning the output of the PHP script in 2 below. The key part is that it needs to be always checking if a value exists in the data base, and not display the form if it doesn't - but it can't make the form reset every time it refreshes. This might be achieved through the PHP output below. 2. A very simple PHP script which checks for a value in the data base, and displays a form. For the purpose of this, it's fine if you just make it display a simple check box with some text and a submit button. 3. I DON'T need it linked to MySQL. I know how to do that and can do all that later. I just need two simple scripts which I can use as a template. I'll plug it in myself, and if it doesn't work, I'll send you a chat. I'm sure this will only take someone 10 mins to do, but I don't know how to do it.