问题
I have found this Q-A Why does ActiveRecord in Rails not support Multiple Table Inheritance?
And now i have a question according to CdotStrifeVII's answer
Polymorphic associations fill that role for most use cases
do you agree with this?
As for me, polymorphic is more like STI implementation...
How rails polymorphic mechanism can be used to implement MTI?
来源：https://stackoverflow.com/questions/40073707/how-activerecord-polymorphic-mechanism-can-be-used-for-mti-implementation