require 'rubygems'
require_gem 'activerecord'
ActiveRecord::Base.establish_connection(
  :adapter  => 'mysql',
  :host     => 'localhost',
  :database => 'myproject_development',
  :username => 'myusername',
  :password => 'mypassword')
# Produces: ./update.rb:24:Warning: require_gem is obsolete.  Use gem instead.

# Okay so then I change it:
require 'rubygems'
gem 'activerecord'
ActiveRecord::Base.establish_connection(
  :adapter  => 'mysql',
  :host     => 'localhost',
  :database => 'myproject_development',
  :username => 'myusername',
  :password => 'mypassword')
# Produces: ./update.rb:33: uninitialized constant ActiveRecord (NameError)