CODEWITHSUNDEEP
ruby-on-rails
max pleaner
max pleaner

Reputation: 26758

cannot rollback migration with rake db:rollback

I guess this is another reason I should be backing up my work with GitHub, but alas, I have not been.

The migration I want to rollback is this: 

class AddAssociationToTables < ActiveRecord::Migration
  def change
        add_column :articles, :user, :belongs_to
  end
end

Which obviously isn't well formed because it seems to have totally removed my article table from the database. I tried rake db:rollback:status and there is nothing 'missing' or anything.

I'm gonna skip copy-pasting the entire trace.

I tried to make a counteracting migration and run that. This is what I wrote: 

class RemoveAssociationFromArticle < ActiveRecord::Migration
  def change
                remove_column :articles, :user, :belongs_to
  end
end

But when I tried to run rake db:migrate with this I got what looks like the same error.

EDIT ok here's the whole trace for the rollback first, and then the migrate attempt

==  AddAssociationToTables: reverting =========================================
-- remove_column(:articles, :user, :belongs_to)
rake aborted!
An error has occurred, this and all later migrations canceled:

undefined method `to_sym' for nil:NilClass/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/schema_definitions.rb:215:in `column'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:545:in `block (2 levels) in copy_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:538:in `each'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:538:in `block in copy_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/schema_statements.rb:184:in `create_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:535:in `copy_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:528:in `move_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:521:in `block in alter_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:200:in `transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:520:in `alter_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:463:in `remove_column'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:625:in `block in method_missing'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:597:in `block in say_with_time'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:597:in `say_with_time'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:617:in `method_missing'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:462:in `block in revert'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:461:in `each'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:461:in `revert'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:569:in `exec_migration'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:555:in `block (2 levels) in migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:554:in `block in migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/connection_pool.rb:294:in `with_connection'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:553:in `migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:709:in `migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:959:in `block in execute_migration_in_transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:1005:in `block in ddl_transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:202:in `block in transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:210:in `within_new_transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:202:in `transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/transactions.rb:209:in `transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:1005:in `ddl_transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:958:in `execute_migration_in_transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:920:in `block in migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:916:in `each'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:916:in `migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:771:in `down'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:857:in `move'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:753:in `rollback'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/railties/databases.rake:126:in `block (2 levels) in <top (required)>'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/bin/ruby_executable_hooks:15:in `eval'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/bin/ruby_executable_hooks:15:in `<main>'
Tasks: TOP => db:rollback
(See full trace by running task with --trace)


==  RemoveAssociationFromArticle: migrating ===================================
-- remove_column(:articles, :user, :belongs_to)
rake aborted!
An error has occurred, this and all later migrations canceled:

undefined method `to_sym' for nil:NilClass/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/schema_definitions.rb:215:in `column'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:545:in `block (2 levels) in copy_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:538:in `each'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:538:in `block in copy_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/schema_statements.rb:184:in `create_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:535:in `copy_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:528:in `move_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:521:in `block in alter_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:200:in `transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:520:in `alter_table'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/sqlite3_adapter.rb:463:in `remove_column'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:625:in `block in method_missing'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:597:in `block in say_with_time'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:597:in `say_with_time'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:617:in `method_missing'
/home/macs/code/my_apps/rails_apps/satisfactory/dec1/whatis/db/migrate/20131202144933_remove_association_from_article.rb:3:in `change'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:571:in `exec_migration'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:555:in `block (2 levels) in migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:554:in `block in migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/connection_pool.rb:294:in `with_connection'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:553:in `migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:709:in `migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:959:in `block in execute_migration_in_transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:1005:in `block in ddl_transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:202:in `block in transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:210:in `within_new_transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:202:in `transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/transactions.rb:209:in `transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:1005:in `ddl_transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:958:in `execute_migration_in_transaction'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:920:in `block in migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:916:in `each'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:916:in `migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:764:in `up'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/migration.rb:742:in `migrate'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/gems/activerecord-4.0.1/lib/active_record/railties/databases.rake:42:in `block (2 levels) in <top (required)>'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/bin/ruby_executable_hooks:15:in `eval'
/home/macs/.rvm/gems/ruby-2.0.0-p247@railstutorial_rails_4_0/bin/ruby_executable_hooks:15:in `<main>'
Tasks: TOP => db:migrate
(See full trace by running task with --trace)

Upvotes: 0

Views: 1221

Answers (2)

AJcodez
AJcodez

Reputation: 34146

If it did not migrate properly in the first place, don't worry about rolling back. Just fix the migration and try to migrate again.

Your migration should be:

add_column :articles, :user, :references

The belongs_to is for in the model class, and not in the migration. If it gets to a point where you can't do anything, you can always recreate the database to start fresh (and lose all data).

$ rake db:drop db:create db:migrate

Start using version control, and read through all of this slowly and carefully at some point in life http://guides.rubyonrails.org/migrations.html

Upvotes: 1

Rodrigo
Rodrigo

Reputation: 4802

The third parameter should be the type of column.

The correct syntax is: 

add_column :articles, :user_id, :integer

The :belongs_to parameter may causing conflict with ActiveRecord methods!

Upvotes: 1

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