Originally posted by TomazZ
Somehow means that it's implicitly converted to characters.
If you input to_date function a date format that is compatible with default setting (used for implicit to_char conversion), it gives no error.
Wasn't sure about that and didn't have time to experiment till I got home. Here it's under 7.3.4:
Code:
SQL> select sysdate from dual;

SYSDATE
---------
04-JUL-03

SQL> select to_date(sysdate,'DD-MM-RRRR') from dual;
ERROR:
ORA-01858: a non-numeric character was found where a numeric was expected
This is the kind of error I expected - due to a mismatch between MM and MON ('DD-MON-RRRR' works OK). Do vsn's 8+ do better?