14일차 # 5-5: 세션의 현재 날짜 및 시간 관련함수들

  * current_date      : DATE (in the session time zone)

  * current_timestamp : TIMESTAMP WITH TIME ZONE (in the session time zone)

  * localtimestamp    : TIMESTAMP (in the session time zone)

   cf.) sysdate      : DATE (for the OS where the database server resides)

    - sysdate vs. current_date

alter session set time_zone = 'Asia/Seoul';

select sysdate as Server, current_date as "Session" from dual;

alter session set time_zone = '-10:00';

select sysdate as Server, current_date as "Session" from dual;

alter session set time_zone = '+03:00';

select sysdate as Server, current_date as "Session" from dual;

    - current_date vs. current_timestamp vs. localtimestamp

col current_date format a25

col current_timestamp format a35

col localtimestamp format a25

alter session set time_zone = '+09:00';

select current_date, current_timestamp, localtimestamp from dual;

alter session set time_zone = '+03:00';

select current_date, current_timestamp, localtimestamp from dual;