diff options
Diffstat (limited to 'guides/source/migrations.textile')
| -rw-r--r-- | guides/source/migrations.textile | 17 |
1 files changed, 8 insertions, 9 deletions
diff --git a/guides/source/migrations.textile b/guides/source/migrations.textile index c11f8e221b..f663496854 100644 --- a/guides/source/migrations.textile +++ b/guides/source/migrations.textile @@ -51,7 +51,7 @@ end This migration adds a table called +products+ with a string column called +name+ and a text column called +description+. A primary key column called +id+ will -also be added, however since this is the default we do not need to ask for this. +also be added, however since this is the default we do not need to explicitly specify it. The timestamp columns +created_at+ and +updated_at+ which Active Record populates automatically will also be added. Reversing this migration is as simple as dropping the table. @@ -65,7 +65,7 @@ class AddReceiveNewsletterToUsers < ActiveRecord::Migration change_table :users do |t| t.boolean :receive_newsletter, :default => false end - User.update_all ["receive_newsletter = ?", true] + User.update_all :receive_newsletter => true end def down @@ -497,7 +497,7 @@ and h4. Using the +change+ Method The +change+ method removes the need to write both +up+ and +down+ methods in -those cases that Rails know how to revert the changes automatically. Currently, +those cases that Rails knows how to revert the changes automatically. Currently, the +change+ method supports only these migration definitions: * +add_column+ @@ -635,10 +635,9 @@ example, $ rake db:migrate:up VERSION=20080906120000 </shell> -will run the +up+ method from the 20080906120000 migration. These tasks still -check whether the migration has already run, so for example +db:migrate:up -VERSION=20080906120000+ will do nothing if Active Record believes that -20080906120000 has already been run. +will run the +up+ method from the 20080906120000 migration. This task will first +check whether the migration is already performed and will do nothing if Active Record believes +that it has already been run. h4. Changing the output of running migrations @@ -728,7 +727,7 @@ class AddFlagToProduct < ActiveRecord::Migration def change add_column :products, :flag, :boolean Product.all.each do |product| - product.update_attributes!(:flag => 'false') + product.update_attributes!(:flag => false) end end end @@ -804,7 +803,7 @@ class AddFlagToProduct < ActiveRecord::Migration end def change - add_column :products, :flag, :integer + add_column :products, :flag, :boolean Product.reset_column_information Product.all.each do |product| product.update_attributes!(:flag => false) |