My team needs to get SQL Server as our backend database. I would like to find out if we should get 2014 or 2012 R2. The rest of the company is probably still SQL Server 2008 R2, Oracle and probably MySQL. I wonder if we get 2014 version which is 2 generations ahead of the 2008 version, would that cause any problem? We will mostly get data from the other databases from other departments of the company.

Another question about version 2012 is that I was told that I should purchase 2014 but download 2012. I would like to find out if the serial number for 2014 can be applied to 2012. I am not sure why I need to purchase 2014 but download 2012 instead.

Please advise! Thank you!