module ActiveRecord::AttributeMethods::Read

def _read_attribute(attr_name, &block) # :nodoc:

:nodoc:
breaking compatibility with the read_attribute API
This method exists to avoid the expensive primary_key check internally, without 
def _read_attribute(attr_name, &block) # :nodoc:
  @attributes.fetch_value(attr_name, &block)
end

def read_attribute(attr_name, &block)

to a date object, like Date.new(2004, 12, 12)).
it has been typecast (for example, "2004-12-12" in a date column is cast
Returns the value of the attribute identified by attr_name after 
def read_attribute(attr_name, &block)
  name = attr_name.to_s
  name = self.class.attribute_aliases[name] || name
  name = @primary_key if name == "id" && @primary_key
  @attributes.fetch_value(name, &block)
end