text: select add_months(date '2021-02-14', 1)                         as add_months_fun,
         current_date                                             as current_date_fun,
         current_timestamp                                        as current_timestamp_fun,
         sysdate                                                  as sysdate_fun,
         systimestamp                                             as systimestamp_fun,
         months_between(date '2021-02-14', date '2021-03-31')     as months_between_fun,
         to_char(date '2021-02-14', 'DD/MON/YYYY')                 as to_char_fun,
         to_timestamp('14/02/21 07:01:00', 'DD/MM/YY HH24:mi:ss') as to_timestamp_fun,
         to_date('14/02/2021', 'DD/MM/YYYY')                      as to_date_fun
  from dual;
  