I don't know of any declarative tools, although I've written some tips on using Rails migrations here: http://illuminatedcomputing.com/posts/2013/03/rules-for-

I don't know of any declarative tools, although I've written some tips on using Rails migrations here: http://illuminatedcomputing.com/posts/2013/03/rules-for-rails-migrations/ http://illuminatedcomputing.com/posts/2013/03/rules-for-rail... The problem with a declarative tool is managing change over time. What happens when you want to change a relationship from one-to-many to many-to-many? How does the declarative tool know how to migrate the old data? There are lots of examples where you need to say specifically how to get from point A to point B, especially once you're in production and can't just throw everything away and start over.