How to delete migration files in Rails 3

user_2587695 0
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I would like to remove/delete a migration file. How would I go about doing that? I know there are similar questions on here but as an update, is there a better way than doing script/destroy?

Also, should I do a db:reset or db:drop if I remove/delete a migration?

ruby-on-rails-3 file-io ruby-on-rails
11 Answers

None of these answers quite fit the problem i had as the migration i wanted to delete was missing: I had created and run a migration in some other branch, which was then discarded. The problem is when a migration is run, rails adds the version into a schema_migrations table in the database. So even if it isn't listed in your db structure or schema, rails looks for it. You can reveal these orphaned migrations by running:

rails db:migrate:status

Note the versions of the missing migrations and head into the db console:

rails dbconsole

Now remove the versions from the migration table manually:

delete from schema_migrations where version='<version>';

You should now be good.

user_29637030

This also works in Rails 5.

If the migration was the most recent one you can remove the database column(s) that the migration added by doing: 

rake db:rollback

then remove the migration file itself by running:

rails d migration WhateverYourMigrationWasNamed.rb
user_85607090

Side Note: Starting at rails 5.0.0 rake has been changed to rails So perform the following

rails db:migrate VERSION=0

user_121890760
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