Pls answer this date question

Question

--pls see this code
create table tdate
(name varchar2(5),
tdate date);
insert into tdate
values ('mat', to_date('26 may 49','DD month yy'));
insert into tdate
values ('kris', to_date('26 may 49','DD month rr'));
select name, to_char(tdate, 'DD Month YYYY HH:MM:SS') as hiredate
from tdate;
--Remember the current sysdate is 26-may-2050
--Can someone tell me what wud be the output of this query.
--Ofcourse I can run this and see myself but I m not able to change the sysdate to year 2050 (Apache server and database service r being shut down automatically when i try to do this ,dont know why.)
-- According to the textbook from oracle I m currently going through.....the output should be...
mat 26 May 2049 07:17:00
kris 26 May 2149 07:17:00 (because of using rr)
about rr format it says-if the current century is in range 50-99 and the entered century is in range 0-49 then the recorded date would be in the century next to the current one.
--pls help me out.Thanx                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           

Answer 1

The RR datetime format element is similar to the YY datetime format element, but it provides additional flexibility for storing date values in other centuries. The RR datetime format element lets you store 20th century dates in the 21st century by specifying only the last two digits of the year.
If you use the TO_DATE function with the YY datetime format element, then the year returned always has the same first 2 digits as the current year. If you use the RR datetime format element instead, then the century of the return value varies according to the specified two-digit year and the last two digits of the current year.
That is:
If the specified two-digit year is 00 to 49, then
If the last two digits of the current year are 00 to 49, then the returned year has the same first two digits as the current year.
If the last two digits of the current year are 50 to 99, then the first 2 digits of the returned year are 1 greater than the first 2 digits of the current year.
If the specified two-digit year is 50 to 99, then
If the last two digits of the current year are 00 to 49, then the first 2 digits of the returned year are 1 less than the first 2 digits of the current year.
If the last two digits of the current year are 50 to 99, then the returned year has the same first two digits as the current year.
The following examples demonstrate the behavior of the RR datetime format element.
RR Datetime Format Examples
Assume these queries are issued between 1950 and 1999:
SELECT TO_CHAR(TO_DATE('27-OCT-98', 'DD-MON-RR') ,'YYYY') "Year"
FROM DUAL;
Year
1998
SELECT TO_CHAR(TO_DATE('27-OCT-17', 'DD-MON-RR') ,'YYYY') "Year"
FROM DUAL;
Year
2017
Now assume these queries are issued between 2000 and 2049:
SELECT TO_CHAR(TO_DATE('27-OCT-98', 'DD-MON-RR') ,'YYYY') "Year"
FROM DUAL;
Year
1998
SELECT TO_CHAR(TO_DATE('27-OCT-17', 'DD-MON-RR') ,'YYYY') "Year"
FROM DUAL;
Year
2017