php - new comments notification implementation for a web site -

I have found a website where people can post and comment on them. I want to create a new comment notification system, so when a user logs, he can see the number of new comments on his posts.

My idea is to add 'Read' table, where I will store user_id and comment_id (read user_id read comment_id).

What is the best way to implement it?

A method for achieving this is the date created for the post and comment and the "last visit" for the user. "To save the date (or" last clicked on user "by clicking on" Show me new post "link).

Then, you just need to get all the posts and comments that the user table Has a new date you received.