What is the best way to use data aggregation of two fields?

Question

Django

There is a number of likes and a number of dislikes. Posts are displayed on the top feed by the difference between likes (the 'like' field) and dislikes (the 'dislike' field). Which is better: 1) annotate(count=F('like')-F('dislike')).order_by("-count") or 2) add a third count field, override save, write the difference to count, and then output by count ?
The site is the first in life, there will be few requests, but I want to know how best for the future.
Thank you!