How to force Google to update KML cache on their servers?
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I am generating a KML file with data from a MySQL database. It is basically a lat/long data with timestamp. It's an online transactions database. I am trying to display only the last 10 transactions. Everything works fine in the Google Earth app but when I try to display the same data from the KML using the web browser plugin for Google Earth, it displays the cached data on Google's servers and so the data is not realtime. 

My refreshInterval is set to 20 secs. I have tried to add dummy string at the end of URL but it is not working. Are there are better ways to do that? Any advice would be appreciated. Thanks!