Use jquery ajax to refresh PHP data on the same page

I have a PHP page with a mysql connection, a select query and then i'm building a table using PHP. If i wanted to use jQuery AJAX to refresh the data on a setInterval, on the same page, how would i go about doing that? (by the way i can do it to another PHP page but i've never done it if the PHP stuff is on the same page)

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If you want to keep making ajax calls i suggest you do long polling, which basically means you have a script that is requesting content via ajax every given time, and it will verify every time if the content has been modified, if not it will wait again and make another call.