java-filmorate

INSERT INTO Friends (user_id, friend_id, is_accepted) VALUES (1, 2, true); - добавление в друзья

DELETE FROM Friends WHERE user_id = 1; - удаление из друзей

SELECT * FROM User; - возвращаем список пользователей

SELECT * FROM Film; - GET allFilms

SELECT u.name FROM User AS u WHERE id IN (SELECT friend_id FROM Friends WHERE friend_id = u.id); - список друзей, общих с другим пользователем

INSERT INTO Likes (film_id, user_id) VALUES (1, 2); - добавление лайка

DELETE FROM Likes WHERE film_id=1 AND user_id=2; - удаление лайка

SELECT f.name, COUNT(l.film_id) amount_of_likes FROM film AS f INNER JOIN likes AS l ON l.film_id=f.id GROUP BY l.film_id ORDER BY amount_of_likes LIMIT 10; - показать самые популярные фильмы