text: INSERT INTO schedules (ID_user, day, start_time, end_time)
  VALUES ('1', '4', '1100', '1430');
  INSERT INTO schedules(ID_user, day, start_time, end_time)
  VALUES ('2', '1', '0900', '1200');
  INSERT INTO schedules(ID_user, day, start_time, end_time)
  VALUES ('3', '5', '1300', '1500');
  
  