Show Pending Migrations

Rails comes with a built-in rake task that allows you to check the status of migrations in the project.

$ rake db:migrate:status

database: pokemon_development

 Status   Migration ID    Migration Name
--------------------------------------------------
   up     20150219143706  Create pokemon table
  down    20150228003340  Create stats table

For large projects with lots of migrations, this is going to be a lot of output, so you can trim it down with a simple grep:

$ rake db:migrate:status | grep '^  down'
  down    20150228003340  Create stats table