select first_name as "Имя", last_name as "Фамилия", salary as "Оклад",sysdate,
to_char(hire_date,'DD.MM.YYYY') as "Дата приема на работу",
trunc(months_between(sysdate, hire_date)) as "Проработано месяцев"
from employees
order by trunc(months_between(sysdate, hire_date))