CODEWITHSUNDEEP
ruby-on-railsruby-on-rails-3activerecord
David Nix
David Nix

Reputation: 3334

How do I fix migrations so rake db:migrate works again

The original issue is that some migration files were originally run on a machine (like production). Later, a few migrations were somehow deleted and could not be recovered.

So, to get a new machine up and running with the app, I had to manually recreate the missing migrations.

Thus, a machine that already performed the deleted migrations is now throwing these errors.

PG::Error: ERROR: relation "some_relation" already exists

I can't just db:reset the db on production because I can't lose that data.

When I run, rake db:test:prepare something like this shows up:

You have 4 pending migrations:
  20130112203055 CreateSomeTable
  20130113180203 AddSomeColumnToTable
  20130113204017 ChangeSomeOtherColumns
  20130311203729 CreateAnotherTable
Run `rake db:migrate` to update your database then try again.

Obviously, running db:migrate will give the PG::Error as stated above. The problem is the schema changes have already been completed via the deleted migrations. The above 'pending' migrations had to be recreated after the fact.

Is there a way to fix this so db:migrate works again?

Upvotes: 0

Views: 1236

Answers (1)

Sri
Sri

Reputation: 2273

Try the following,

rake db:migrate:down VERSION=20121031XXXXXXXX
rake db:migrate

Where 20121031XXXXXXXX is the date stamp of the migration name. In other words, you'll have a migration named 20120410214815_some_relation.rb (like) and you copy the date stamp from the filename and paste it into the command. Here's the Rails Guide on Migrations for reference.

Upvotes: 1

Related Questions