rename_column :table, :old_column, :new_column
You'll probably want to create a separate migration to do this. (Rename FixColumnName
as you will.):
script/generate migration FixColumnName
# creates db/migrate/xxxxxxxxxx_fix_column_name.rb
Then edit the migration to do your will:
# db/migrate/xxxxxxxxxx_fix_column_name.rb
class FixColumnName < ActiveRecord::Migration
def self.up
rename_column :table_name, :old_column, :new_column
end
def self.down
# rename back if you need or do something else or do nothing
end
end
For Rails 3.1 use:
While, the up
and down
methods still apply, Rails 3.1 receives a change
method that "knows how to migrate your database and reverse it when the migration is rolled back without the need to write a separate down method".
See "Active Record Migrations" for more information.
rails g migration FixColumnName
class FixColumnName < ActiveRecord::Migration
def change
rename_column :table_name, :old_column, :new_column
end
end
If you happen to have a whole bunch of columns to rename, or something that would have required repeating the table name over and over again:
rename_column :table_name, :old_column1, :new_column1
rename_column :table_name, :old_column2, :new_column2
...
You could use change_table
to keep things a little neater:
class FixColumnNames < ActiveRecord::Migration
def change
change_table :table_name do |t|
t.rename :old_column1, :new_column1
t.rename :old_column2, :new_column2
...
end
end
end
Then just db:migrate
as usual or however you go about your business.
For Rails 4:
While creating a Migration
for renaming a column, Rails 4 generates a change
method instead of up
and down
as mentioned in the above section. The generated change
method is:
$ > rails g migration ChangeColumnName
which will create a migration file similar to:
class ChangeColumnName < ActiveRecord::Migration
def change
rename_column :table_name, :old_column, :new_column
end
end
I would recommend dropping your test database, then re-create it and migrate:
bundle exec rake db:drop RAILS_ENV=test
bundle exec rake db:create RAILS_ENV=test
bundle exec rake db:schema:load RAILS_ENV=test
After these steps you can run your specs:
bundle exec rspec spec
gerry3 noted that:
A simpler solution is to just run rake db:test:prepare
However, if you're using PostgreSQL this wont work because the rails environment gets loaded, which opens a database connection. This causes the prepare
call to fail, because the DB cannot be dropped. Tricky thing.
Best Answer
CONGRATULATIONS on you endeavor into TDD with ROR I promise once you get going you will not look back.
The simplest quick and dirty solution will be to generate a new valid model before each of your tests like this:
BUT what I suggest is you set up factories for all your models that will generate a valid model for you automatically and then you can muddle with individual attributes and see if your validation. I like to use FactoryGirl for this:
Basically once you get set up your test would look something like this:
Oh ya and here is a good railscast that explains it all better than me:
good luck :)
UPDATE: As of version 3.0 the syntax for factory girl has changed. I have amended my sample code to reflect this.