Rails migrations in non-Rails (and non Ruby) projects.

WHAT'S NEW

In the 1.0 release we have moved to using Rails 3 migrations instead of maintaining our own migration related code. Just about anything you can do with Rails 3 migrations you can now do with Standalone Migrations too! This removed 95% of the code we have to maintain. Big thanks to Michael Grosser for undertaking this major rewrite!

CONTRIBUTE

Standalone Migrations relies on the contributions of the open-source community! To submit a fix or an enhancement fork the repository, checkout the develop branch, make your changes, add your name to the Contributors section in README.markdown, and send us a pull request! If you're active and do good work we'll add you as a collaborator!

USAGE

Install Ruby, RubyGems and a ruby-database driver (e.g. gem install mysql) then:

sudo gem install standalone_migrations

Add to Rakefile in your projects base directory:

begin
  require 'tasks/standalone_migrations'
rescue LoadError => e
  puts "gem install standalone_migrations to get db:migrate:* tasks! (Error: #{e})"
end

Add database configuration to db/config.yml in your projects base directory e.g.:

development:
  adapter: sqlite3
  database: db/development.sqlite3
  pool: 5
  timeout: 5000

production:
  adapter: mysql
  encoding: utf8
  reconnect: false
  database: somedatabase_dev
  pool: 5
  username: root
  password:
  socket: /var/run/mysqld/mysqld.sock

test: &test
  adapter: sqlite3
  database: db/test.sqlite3
  pool: 5
  timeout: 5000

To create a new database migration:

rake db:new_migration name=FooBarMigration
edit db/migrate/20081220234130_foo_bar_migration.rb

... and fill in the up and down migrations Cheatsheet.

If you really want to, you can just execute raw SQL:

def self.up
  execute "insert into foo values (123,'something');"
end

def self.down
  execute "delete from foo where field='something';"
end

Even better, you can use the generate task to create the initial migration

The general form is:

rake db:generate model="model_name" fields="type:column_name0 type:column_name1 ... type:column_namen"

You can have as many fields as you would like.

An example to create a Person table with 3 columns (and it will automatically add the t.timestamps line)

rake db:generate model="Person" fields="string:first_name string:last_name integer:age"

This will create a migration in db/migrate/

class CreatePerson < ActiveRecord::Migration
  def self.up
    create_table :Person do |t|
      t.string :first_name
      t.string :last_name
      t.integer :age
      t.timestamps
    end
  end

  def self.down
    drop_table :Person
  end
end

To apply your newest migration:

rake db:migrate

To migrate to a specific version (for example to rollback)

rake db:migrate VERSION=20081220234130

To migrate a specific database (for example your "testing" database)

rake db:migrate DB=test ... or ...
rake db:migrate RAILS_ENV=test

To execute a specific up/down of one single migration

rake db:migrate:up VERSION=20081220234130

To revert your last migration

rake db:rollback

To revert your last 3 migrations

rake db:rollback STEP=3

Custom configuration

By default, Standalone Migrations will assume there exists a "db/" directory in your project. But if for some reason you need a specific directory structure to work with, you can use a configuration file named .standalone_migrations in the root of your project containing the following:

db:
    seeds: db/seeds.rb
    migrate: db/migrate
    schema: db/schema.rb
config:
    database: db/config.yml

These are the configurable options available. You can omit any of the keys and Standalone Migrations will assume the default values.

Contributors

• Todd Huss
• Two Bit Labs
• Michael Grosser
• Eric Lindvall
• Steve Hodgkiss
• Rich Meyers
• Wes Bailey
• Robert J. Berger
• Federico Builes
• Ricardo Valeriano

This work is originally based on Lincoln Stoll's blog post and David Welton's post.