Favorite/unfavorite sounds

migrations/20230816145151_favorite_sounds.sql

@@ -0,0 +1,8 @@
+ALTER TABLE users ADD PRIMARY KEY (`user`);
+
+CREATE TABLE favorite_sounds (
+    user_id BIGINT UNSIGNED NOT NULL,
+    sound_id INT UNSIGNED NOT NULL,
+    FOREIGN KEY (sound_id) REFERENCES `sounds`(`id`) ON DELETE CASCADE ON UPDATE CASCADE,
+    PRIMARY KEY (user_id, sound_id)
+);