The Justin Beiber problem in database design refers to the issue of counting likes on Instagram posts, which can put a strain on the database server.Instead of querying the likes table each time to count the likes, a solution is to have a likes_count column in the posts table.Each time a post is liked, it creates a like record in the database and increments the likes_count column in the posts table.By directly accessing the likes_count column, the application can retrieve the likes count faster and more efficiently.