I currently have a MySQL database which I was hoping to use to store regularly updated data from a temperature sensor connected to the internet.

I currently have a page that, when opened, will grab the current temperature and the current timestamp and add it as an entry to the database, but I was looking for a way to do that without me refreshing the page every 5 seconds.

Detail: The data comes from an Arduino Ethernet, posted to an IP address. Currently, I'm using cURL to grab the data from the IP, add a timestamp and save it to the DB. Obviously only updates when the page is refreshed (it uses PHP).

Here is a live feed of the data - http://wetdreams.org.uk/ChrisProject/UI/live_graph_two.html

TL;DR - Basically I need a middle man to grab the data from the IP and post it to a MySQL

Edit: Thanks for all the advice. There might be a little bit of confusion, I'm looking for a solution that (ideally) doesn't require a computer to be on at all (other than the Server containing Database). Since I'm looking to store data over long periods of time (weeks), I'd like to set it up and leave a script running on the server (or Arduino) that gets the temp and posts it to the Database.

In my head I would like to have a page on the server that automatically (without any browser open, or any other prompting other than a timer) calls a PHP script.

Hope that clears things up!