11일차 # 9-11: Datetime Data Type

  - DATE - TIMESTAMP

          - TIMESTAMP WITH TIME ZONE

          - TIMESTAMP WITH LOCAL TIME ZONE

  - INTERVAL - INTERVAL YEAR TO MONTH

                  - INTERVAL DAY TO SECOND

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

select dbtimezone, sessiontimezone from dual;

drop table t_order purge;

create table t_orders (

 no number(4),

 customer_name varchar2(10),

 order_date1 date,

 order_date2 timestamp,

 order_date3 timestamp with time zone,

 order_date4 timestamp with local time zone);

insert into t_orders values

   (1000, 'Choi', current_timestamp, current_timestamp, 

             current_timestamp, current_timestamp);

select * from t_orders;

alter session set time_zone = '+0:0';

select * from t_orders;

alter session set time_zone = '-2:0';

select * from t_orders;

==> TIMESTAMP WITH LOCAL TIME ZONE은 입력된 시간을 

   DATABASE의 TIMEZONE에 대해 NORMALIZE하여 저장합니다.