date format

[gaurishere]

in insert statement default is used (default '01011901')
even though

show parameter NLS_DATE_FORMAT

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
nls_date_format                      string      DDMMYYYY

i have to used

alter session set nls_date_format='DDMMYYYY';

explain me why this was necessity

[debasisdas]

What exactly you are looking for ?