As great as Rails 2.1 is, I for the life of me cannot figure out why polymorphic associations do not support reconfiguring the type column used.
For example, I have no way to do a polymorphic association using a lookup hash which maps an integer to a class name.
Storing a TINYINT unsigned is waaaaay more efficient than storing a string like "SomeActiveRecordModel" over and over again.
Looking in the association proxy classes for has_one and has_many, I see:
def construct_sql case when @reflection.options[:as] @finder_sql = "#{@reflection.quoted_table_name}.#{@reflection.options[:as]}_id = #{@owner.quoted_id} AND " + "#{@reflection.quoted_table_name}.#{@reflection.options[:as]}_type = #{@owner.class.quote_value(@owner.class.base_class.name.to_s)}" else @finder_sql = "#{@reflection.quoted_table_name}.#{@reflection.primary_key_name} = #{@owner.quoted_id}" end @finder_sql << " AND (#{conditions})" if conditions end
This cannot easily be changed. The type condition should be a function call so we could easily modified. Has anybody thought about this?