Loading data in a Rails migration - ruby-on-rails

Question

I created number of migrations starting with a definition for a Posts table.
class CreatePosts < ActiveRecord::Migration
def self.up
create_table :posts do |t|
t.column "title", :string, :limit => 100, :default => "", :null => false
t.column "content", :text, :null => false
t.column "author", :string, :limit => 100, :default => 0, :null => false
t.column "category", :string, :limit => 20, :default => "", :null => false
t.column "status", :string, :limit => 20, :default => "", :null => false
t.timestamps
end
end
def self.down
drop_table :posts
end
end
And another one for a Users table in which I load some data for a default user after creating the table.
class CreateUsers < ActiveRecord::Migration
def self.up
create_table :users do |t|
t.column "username", :string, :limit => 25, :default => "", :null => false
t.column "hashed_password", :string, :limit => 40, :default => "", :null => false
t.column "first_name", :string, :limit => 25, :default => "", :null => false
t.column "last_name", :string, :limit => 40, :default => "", :null => false
t.column "email", :string, :limit => 50, :default => "", :null => false
t.column "display_name", :string, :limit => 25, :default => "", :null => false
t.column "user_level", :integer, :limit => 3, :default => 0, :null => false
t.timestamps
end
user = User.create(:username => 'bopeep',
:hashed_password => 'bopeep',
:first_name => 'Bo',
:last_name => 'Peep',
:email => 'bo#peep.com',
:display_name => 'Little Bo Peep',
:user_level => 9)
end
def self.down
drop_table :users
end
end
Next I created a migration to alter the Posts table to rename the table to blog_posts. Here I also wanted to load a default blog post entry.
class AlterPosts < ActiveRecord::Migration
def self.up
rename_table :posts, :blog_posts
change_column :blog_posts, :author, :integer, :default => 0, :null => false
rename_column :blog_posts, :author, :author_id
add_index :blog_posts, :author_id
bopeep = User.find_by_username 'bopeep'
BlogPost.create(:title => 'test', :content => 'test', :author_id => bopeep.id, :category => 'test', :status => 'ok')
end
def self.down
remove_index :blog_posts, :author_id
rename_table :blog_posts, :posts
rename_column :posts, :author_id, :author
change_column :posts, :author, :string, :limit => 100, :default => 0, :null => false
end
end
But this generates an error:
uninitialized constant AlterPosts::BlogPost
How should I have loaded the default BlogPost instead of "BlogPost.create"?

Answer 1

Separate your rename_table and your change/rename column migrations into another migration file.
I don't think the rename is committed until after the entire block goes through... and so therefore blog_posts does not exist yet.