To roll back all migrations up to a particular version (e.g. 20181002222222), use:

rake db:migrate VERSION=20181002222222

(Note that this uses db:migrate -- not db:migrate:down as in other answers to this question.)

Assuming the specified migration version is older than the current version, this will roll back all migrations up to, but not including, the specified version.

For example, if rake db:migrate:status initially displays:

  (... some older migrations ...)
  up      20181001002039  Some migration description
  up      20181002222222  Some migration description
  up      20181003171932  Some migration description
  up      20181004211151  Some migration description
  up      20181005151403  Some migration description

Running:

rake db:migrate VERSION=20181002222222

Will result in:

  (... some older migrations ...)
  up      20181001002039  Some migration description
  up      20181002222222  Some migration description
  down    20181003171932  Some migration description
  down    20181004211151  Some migration description
  down    20181005151403  Some migration description

Reference: https://makandracards.com/makandra/845-migrate-or-revert-only-some-migrations

If you using RAILS 3

Step: 1 (Check the last migration)

bundle exec rake db:migrate:status

Step: 2 (Rollback Last Migration)

bundle exec rake db:rollback

Now, you can revert migration with safety One by One.

For Specific Migration

rails d migration <migration_name>

For revert multiple migrations

bundle exec rake db:rollback STEP=n

n = how many migrations do you want to rollback

Example: bundle exec rake db:rollback STEP=5

i found these steps most useful.

To check for status, run rails db:migrate:status. Then you'll have a good view of the migrations you want to remove.

Then, run rails db:rollback to revert the changes one by one. After doing so, you can check the status again to be fully confident.

Next, if you want to remove or delete. Run rails d migration <migration_name>. This would clean up the versions you created.

After that's done, you can proceed to making new changes.

In Addition

When migration you deployed long ago does not let you migrate new one.

What happened is, I work in a larger Rails app with more than a thousand of migration files. And, it takes a month for us to ship a medium-sized feature. I was working on a feature and I had deployed a migration a month ago then in the review process the structure of migration and filename changed, now I try to deploy my new code, the build failed saying

ActiveRecord::StatementInvalid: PG::DuplicateColumn: ERROR:  column "my_new_field" of relation "accounts" already exists

none of the above-mentioned solutions worked for me because the old migration file was missing and the field I intended to create in my new migration file already existed in the DB. The only solution that worked for me is:

1. I scped the file to the server
2. I opened the rails console
3. I required the file in the IRB session
4. then AddNewMyNewFieldToAccounts.new.down

then I could run the deploy build again.

Hope it helps you too.

For multiple databases configurations (RoR >= v6), you must append the database name in the command, like:

• rails db:rollback:primary, where primary is the name of the database in your config/databases.yml file, to rollback the last migration. You can make usage of the STEPS attribute here, as usual.
• rails db:rollback:primary VERSION=your_migration_timestamp, to rollback only the provided migration version. Here primary is the name of the database too.

If you Want to Revert from last Migration Use rake db:rollback command It's Work Fine for Me!