til/rails/rollback-a-couple-migrations.md

Rollback A Couple Migrations

Let's say we need to rollback a couple Rails migrations that have been applied to our local environment. We run rails db:migrate:status and see that there are 2 migrations that we want to undo.

We can accomplish this by using the STEP env var with the rollback command.

$ rails db:rollback STEP=2

Just set STEP to the number of migrations that we need to rollback. If we then rerun rails db:migrate:status we'll now see those latest two migrations are down.

Note: by default Rails doesn't like to operate with pending migrations. If we want to temporarily disable the pending migration check, we can alter the migration error config in config/development.rb.

  # Raise an error on page load if there are pending migrations.
-  # config.active_record.migration_error = :page_load
+  config.active_record.migration_error = false