巢狀留言功能如何設計？

How to design a commenting system that support nested comment?

What is the best solution? for both UI/UX & schema?

dev.to

https://dev.to/sergio/what-is-your-best-advice-for-a-junior-software-developer-32gn

reddit

https://www.reddit.com/r/programming/comments/4jvnl4/programming_doesnt_require_talent_or_even_passion/

quora

https://www.quora.com/Are-there-any-poor-people-on-Quora-as-Internet-access-is-very-cheap-nowadays/answer/Rajana-Siva

disqus

http://blog.turn.tw/?p=1283

questions

1. database schema for this?
2. infinitely nested comment? or limited level?
3. Medium 似乎只能巢狀留言到 1 層？