I've seen it happen once. Back in 2011, the company I was working for decided to switch all of their apps from MySQL to postgres. We had built everything in Dja

I've seen it happen once. Back in 2011, the company I was working for decided to switch all of their apps from MySQL to postgres. We had built everything in Django, so the transition was a lot less painful than it could have been, but it definitely wasn't free.