Run query when user leaves page

Hi, is there a way to run a query when the user has left a specific page.
For example i have a page called "Page1", and the user goes to lets say "Page2" then it would run my delete query
I was thinking of somewhere as to add my query to the page_unload event, but i dont think thats the right event to put it in
Any ideas on how to do this?
Thanks
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