Module ActiveRecord::AttributeMethods::Query

    # File activerecord/lib/active_record/attribute_methods/query.rb, line 12
12:       def query_attribute(attr_name)
13:         unless value = read_attribute(attr_name)
14:           false
15:         else
16:           column = self.class.columns_hash[attr_name]
17:           if column.nil?
18:             if Numeric === value || value !~ /[^0-9]/
19:               !value.to_i.zero?
20:             else
21:               return false if ActiveRecord::ConnectionAdapters::Column::FALSE_VALUES.include?(value)
22:               !value.blank?
23:             end
24:           elsif column.number?
25:             !value.zero?
26:           else
27:             !value.blank?
28:           end
29:         end
30:       end