ruby-1.8.7-p334 :051 > u
 => #<User id: 4, email: "test@test.com", encrypted_password: "$2a$10$Dfdpvgdy6DvMOtn5lNWdAeV0w8wS3JIuZ.8RXrOWZ.Iq...", reset_password_token: nil, remember_created_at: nil, sign_in_count: 1, current_sign_in_at: "2011-04-10 02:43:50", last_sign_in_at: "2011-04-10 02:43:50", current_sign_in_ip: "127.0.0.1", last_sign_in_ip: "127.0.0.1", created_at: "2011-04-10 02:43:50", updated_at: "2011-04-10 02:44:47", username: "test", is_admin: false, is_editor: false>
ruby-1.8.7-p334 :052 > u.is_admin
 => false
ruby-1.8.7-p334 :053 > u.valid?
 => true
ruby-1.8.7-p334 :054 > u.update_attributes({:is_admin => true})
 => true
ruby-1.8.7-p334 :055 > u.is_admin
 => false
ruby-1.8.7-p334 :056 > u.update_attributes!({:is_admin => true})
 => true
ruby-1.8.7-p334 :057 > u.is_admin
 => false
ruby-1.8.7-p334 :058 > User.find(u.id).is_admin?
 => false
ruby-1.8.7-p334 :059 > u.username
 => "test"
ruby-1.8.7-p334 :060 > u.update_attributes({:username => "hello"})
 => true
ruby-1.8.7-p334 :061 > u.username
 => "hello"
ruby-1.8.7-p334 :062 > User.find(u.id).username
 => "hello"
ruby-1.8.7-p334 :063 > u.is_admin?
 => false