diff options
Diffstat (limited to 'activerecord/lib/active_record/migration.rb')
| -rw-r--r-- | activerecord/lib/active_record/migration.rb | 27 |
1 files changed, 12 insertions, 15 deletions
diff --git a/activerecord/lib/active_record/migration.rb b/activerecord/lib/active_record/migration.rb index ca3ca54fa0..80aa123fdd 100644 --- a/activerecord/lib/active_record/migration.rb +++ b/activerecord/lib/active_record/migration.rb @@ -1,6 +1,3 @@ -require 'active_support/core_ext/kernel/singleton_class' -require 'active_support/core_ext/module/aliasing' - module ActiveRecord # Exception that can be raised to stop migrations from going backwards. class IrreversibleMigration < ActiveRecordError @@ -43,11 +40,11 @@ module ActiveRecord # Example of a simple migration: # # class AddSsl < ActiveRecord::Migration - # def self.up + # def up # add_column :accounts, :ssl_enabled, :boolean, :default => 1 # end # - # def self.down + # def down # remove_column :accounts, :ssl_enabled # end # end @@ -63,7 +60,7 @@ module ActiveRecord # Example of a more complex migration that also needs to initialize data: # # class AddSystemSettings < ActiveRecord::Migration - # def self.up + # def up # create_table :system_settings do |t| # t.string :name # t.string :label @@ -77,7 +74,7 @@ module ActiveRecord # :value => 1 # end # - # def self.down + # def down # drop_table :system_settings # end # end @@ -147,11 +144,11 @@ module ActiveRecord # # This will generate the file <tt>timestamp_add_fieldname_to_tablename</tt>, which will look like this: # class AddFieldnameToTablename < ActiveRecord::Migration - # def self.up + # def up # add_column :tablenames, :fieldname, :string # end # - # def self.down + # def down # remove_column :tablenames, :fieldname # end # end @@ -179,11 +176,11 @@ module ActiveRecord # Not all migrations change the schema. Some just fix the data: # # class RemoveEmptyTags < ActiveRecord::Migration - # def self.up + # def up # Tag.find(:all).each { |tag| tag.destroy if tag.pages.empty? } # end # - # def self.down + # def down # # not much we can do to restore deleted data # raise ActiveRecord::IrreversibleMigration, "Can't recover the deleted tags" # end @@ -192,12 +189,12 @@ module ActiveRecord # Others remove columns when they migrate up instead of down: # # class RemoveUnnecessaryItemAttributes < ActiveRecord::Migration - # def self.up + # def up # remove_column :items, :incomplete_items_count # remove_column :items, :completed_items_count # end # - # def self.down + # def down # add_column :items, :incomplete_items_count # add_column :items, :completed_items_count # end @@ -206,11 +203,11 @@ module ActiveRecord # And sometimes you need to do something in SQL not abstracted directly by migrations: # # class MakeJoinUnique < ActiveRecord::Migration - # def self.up + # def up # execute "ALTER TABLE `pages_linked_pages` ADD UNIQUE `page_id_linked_page_id` (`page_id`,`linked_page_id`)" # end # - # def self.down + # def down # execute "ALTER TABLE `pages_linked_pages` DROP INDEX `page_id_linked_page_id`" # end # end |