Sometimes I find that I want pre-load my database with some data, like categories that I have. For testing purposes, I have already created this data in my fixture; now I just want to load that fixture into my database from a migration call.

I know that there is a rake task for this, so I looked into that code and came up with a little something.

require 'active_record/fixtures'

class CreateCategories < ActiveRecord::Migration
  def self.up
    create_table :categories do |t|
      t.column :name, :string
    end

    Fixtures.create_fixtures('test/fixtures', File.basename("categories.yml", '.*'))
  end

  def self.down
    drop_table :categories
  end
end

First I had to require active_record/fixtures. This allows me to call the Fixtures#create_fixtures method, which load my data. Now I can gaurantee that my fixture data will be loaded for any environment.

That sets of the paranoia level up because who knows, I may need 1001 migrations! So to settle this once and for all, I wrote a script that would generate 999 migrations for me. I ran the 1000 migration and then it created 1001_test1001.rb.

Good news! Rails doesn’t constrain its migrations to a 3 decimal place prefix. So pointless…