protip you can specify THOR_DIFF for checking diff. see also: http://qiita.com/ma2ge/items/ a838864f059fc9b931b2 • check the difference • I recommended to use railsdiff.org. http://railsdiff.org/
again and again • solve the dependency problems something like the following • update gems suitable for your new Rails version • if there's nothing for suitable version you can make a pull request or fork • etc...
CreateXxx < ActiveRecord::Migration[5.0] -class CreateXxx < ActiveRecord::Migration[5.1] # plan 2 + t.references :yyy, foreign_key: true - t.references :yyy, type: :integer, foreign_key: true # plan 3 change all old migration to 5.1 if you are developing new project