How to check user action?

Question

Flask

Good evening. I have a small blog written in Python / Flask. I want to implement a post approval system.
Adding likes done, now a bit confused with checking for likes/dislikes by a user of a certain comment. If you already like it, then you can't do it anymore. I am attaching the database structure.
What can you advise?

-Users
--id
--name
--email
--password

-Posts
--id
--title
--description
--author_id

-Comments
--id
--text
--author_name
--post_id
--like

Answer 1

Obviously, if you want to store a user's like for a comment, then there must be a `likes` table with the fields `user_id` and `comment_id` together forming the primary key.
In this case, it will simply not be possible to add two likes of one user to one comment in the database.