<<TableOfContents>>
== Actions ==
 * create_table(name, options)
 * drop_table(name)
 * rename_table(old_name, new_name)
 * add_column(table_name, column_name, type, options)
 * rename_column(table_name, column_name, new_column_name)
 * change_column(table_name, column_name, type, options)
 * remove_column(table_name, column_name)
 * add_index(table_name, column_name, index_type)
 * remove_index(table_name, column_name)

== Columns ==
=== Types ===
integer, float, datetime, date, timestamp, time, text, string, binary and boolean
=== Options ===
 * limit
  {{{ :limit => "50" }}}
 * default
  {{{ :default => "blah" }}}
 * null
  {{{ :null => false }}} implies NOT NULL

== Steps to start a new database ==
=== Create database using DDL ===
{{{
> mysql -u root -p

mysql> create database myproject_development;
mysql> create database myproject_test;
mysql> create database myproject_production;
mysql> grant all on myproject_development.* to 'railsdev'@'localhost';
mysql> grant all on myproject_test.* to 'railsdev'@'localhost';
mysql> grant all on myproject_production.* to 'prod'@'localhost' identified by 'username';
exit
}}}
=== Edit config/database.yml to match ===

=== Generate initial migration script ===
{{{
> ruby script/generate migration initial
}}}
This creates {{{db/migrate/001_initial.rb}}}
=== Edit db/migrate/001_initial.rb ===
{{{
class Initial < ActiveRecord::Migration
  def self.up
    create_table :products do |table|
      table.column :title,       :string, :limit => 100, :null => false      
      table.column :description, :text,                  :null => false      
      table.column :image_url,   :string, :limit => 200, :null => false
      table.column :price,       :float,                 :null => false
    end
  end
  
  def self.down
    drop_table :products
  end
end
}}}

=== Run the migration ===
{{{
> rake db:migrate
}}}
or
{{{
> rake db:migrate version=1
}}}

== See Also ==
 * [[http://weblog.jamisbuck.org/2005/9/27/getting-started-with-activerecord-migrations|Getting started with Migrations]]
 * [[http://garrettsnider.backpackit.com/pub/367902|Garrett Snider's cheat sheet]]
 * [[http://www.rubyrailways.com/ruby-on-rails-migrations|Peter Szinek's first]] and [[http://www.rubyrailways.com/ruby-on-rails-migrations-reloaded/|second]] posts on migrations

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CategoryCheatSheet