# File lib/active_record/attribute_methods/primary_key.rb, line 48 def primary_key @primary_key = reset_primary_key unless defined? @primary_key @primary_key end
# File lib/active_record/attribute_methods/primary_key.rb, line 42 def dangerous_attribute_method?(method_name) super && !['id', 'id=', 'id?'].include?(method_name) end
# File lib/active_record/attribute_methods/primary_key.rb, line 28 def define_method_attribute(attr_name) super if attr_name == primary_key && attr_name != 'id' generated_attribute_methods.send(:alias_method, :id, primary_key) generated_external_attribute_methods.module_eval " def id(v, attributes, attributes_cache, attr_name) attr_name = '#{primary_key}' send(attr_name, attributes[attr_name], attributes, attributes_cache, attr_name) end ", __FILE__, __LINE__ end end
Defines the primary key field -- can be overridden in subclasses. Overwriting will negate any effect of the primary_key_prefix_type setting, though.
# File lib/active_record/attribute_methods/primary_key.rb, line 48 def primary_key @primary_key = reset_primary_key unless defined? @primary_key @primary_key end
Sets the name of the primary key column.
class Project < ActiveRecord::Base self.primary_key = "sysid" end
You can also define the #primary_key method yourself:
class Project < ActiveRecord::Base def self.primary_key "foo_" + super end end Project.primary_key # => "foo_id"
# File lib/active_record/attribute_methods/primary_key.rb, line 101 def primary_key=(value) @original_primary_key = @primary_key if defined?(@primary_key) @primary_key = value && value.to_s @quoted_primary_key = nil end
Returns a quoted version of the primary key name, used to construct SQL statements.
# File lib/active_record/attribute_methods/primary_key.rb, line 54 def quoted_primary_key @quoted_primary_key ||= connection.quote_column_name(primary_key) end