Why does SQL 2008 all of a sudden want to drop my tables when I go to change the column type from say int to real? This never happened in SQL 2005 to my knowledge. Any insight would be helpful please.
In SQL Server 2008, go to Tools >> Options. In the little window, click "Designer". Uncheck "Prevent saving changes that require ..."
=====
Edited on Sept 4th, 2015.
I have added this answer here a long, long time ago describing the way I would solve the situation described on the question above. Since then, users on the threads below have exposed several concerns on doing things the way I recommended at the time. Basically, the solution I described could be problematic on some scenarios. I then suggest you to keep on reading to check other users' comments and pick the best solution for you.