mysql drop table ER_ROW_IS_REFERENCED: Cannot delete or update a parent row: a foreign key constraint fails code example

Example: Cannot delete or update a parent row: a foreign key constraint fails (

ALTER TABLE "appointments" DROP FOREIGN KEY "appointments_user_id_foreign";

ALTER TABLE "appointments" ADD CONSTRAINT "appointments_user_id_foreign" FOREIGN KEY ("user_id") REFERENCES "users" ("id") ON DELETE CASCADE;