Rails 4 how to ignore pending migrations

Problem is following:

• I have db/seed.rb full of initial data.
• One of migrations depends on data this seed provides.
• I'm trying to deploy my app from empty db.

Result is:

• RAILS_ENV=production rake db:migrate - fails due to lack of initial data
• RAILS_ENV=production rake db:seed - fails due to pending migrations

I wanted to somehow tell rake to ignore pending migrations, but unable to do it so far.

UPDATE (due to additional experience)

Sometimes migrations and model code goes out of sync, so migrations not being run. To avoid this problem recently used redefining of model in migrations:

# reset all callbacks, hooks, etc for this model
class MyAwesomeModel < ActiveRecord::Base
end

class DoSomethingCool < ActiveRecord::Migration
  def change
    ...
  end
end

I am not very sure if this will help you. But I was looking for something and found this question. So it looks like this might help:

In RAILS_ROOT/config/environments/development.rb Set the following setting to false:

 config.active_record.migration_error = false#:page_load

In my situation it now does not show the pending migration error anymore. Should work for rake tasks and console for the same environment as well.

Rename the migration dependent on the data from:

20140730091353_migration_name.rb

to

.20140730091353_migration_name.rb

(add a dot at the start of the filename)

Then run rake db:seed (it will no longer complain on the pending migrations) and then rename back the migration.

If you have more migrations following after, you have to rename all of them or just move it temporary away.

Rails stores migration information in a table called schema_migrations.

You can add the version from your migration into that table to skip a specific migration.

The version is the number string which comes before the description in the file name.

[version]_Create_Awesome.rb

I had a similar issue. I commented out the add_column lines and ran the rake db:migrate commands and then removed the comment when I will need it for the testing or production environment.

There is no way unless you monkey patch the Rails code. I strongly advise you to fix your migrations instead.

A migration should not depend on the existence of some data in the database. It can depend on a previous migration, but of course absolutely not on the data on the db.

If you came across the "pending migrations" issue when trying to seed your data from within a running Rails application, you can simply call this directly which avoids the abort_if_pending_migrations check:

ActiveRecord::Tasks::DatabaseTasks.load_seed

See where seeds are actually called from within ActiveRecord:

https://github.com/rails/rails/blob/v6.0.3.2/activerecord/lib/active_record/railties/databases.rake#L331

and see the DatabaseTasks docs:

https://apidock.com/rails/v6.0.0/ActiveRecord/Tasks/DatabaseTasks https://apidock.com/rails/v6.0.0/ActiveRecord/Tasks/DatabaseTasks/load_seed