"Josh Breckman worked for a company that landed a contract to develop a content management system for a fairly large government website. Much of the project involved developing a content management system so that employees would be able to build and maintain the ever-changing content for their site.
Things went pretty well for a few days after going live. But, on day six, things went not-so-well: all of the content on the website had completely vanished and all pages led to the default "please enter content" page. Whoops.
Josh was called in to investigate and noticed that one particularly troublesome external IP had gone in and deleted *all* of the content on the system. The IP didn't belong to some overseas hacker bent on destroying helpful government information. It resolved to googlebot.com, Google's very own web crawling spider. Whoops.
And something else: according to the HTTP 1.1 specification, the GET method is defined as a Safe Method which "SHOULD NOT have the significance of taking an action other than retrieval." If you to change a state (delete content, replace data), you should use POST.
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Google Deleted... Google Blog
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