In Active Record when updating records I used to have an very manual process to this some thing like:

@todo.done = params['post']['done']
@todo.desc = params['post']['desc']
@todo.save

Model of Todo with boolean done and text description field.

This can be done in a more maintainable fashion with:

@todo.update_attributes = params['post']

This does pose the security concern that the form (which transmits params[‘post’]) could be hacked to add id fields or such like that you may get unwanted manipulation of the table.

To solve this there is a attr_accessible which specifies fields allowed to be updated by the .attributes . while this might seem now like there is no benefit as if we run a migration to add an extra column we also need to update the Active Record model. While this is true we only need to update the model once and create/new and update methods should benefit from this.

class Todo < ActiveRecord::Base
end

Becomes

class Todo < ActiveRecord::Base
   attr_accessible :done
   attr_accessible :desc
end

Summary:

@customer.update_attributes = { "description" => "Jolly fellow", "credit_rating" => "Superb" }

same as:

@customer.description = "Jolly fellow"
@customer.credit_rating = "Superb"
@customer.save