Date Format (Need result in date format)

Question

Dear ,
i have worked on this query which produce result in error, infact i need result in date format and this format 'MON-YY'. :
select to_date( EFFECTIVE_DATE,'MON-YY' ) as MON_YY FROM GL_JE_LINES
but now EFFECTIVE_DATE is like this format '12/31/2008'

Answer 1

I tell again: a date has no internal format.
There is only a default output-format for date-objects wich is used as default output format and for implicit date conversions.
If you want to know the actual nls_date_format for your session you can use:
select * from nls_session_parameters where parameter='NLS_DATE_FORMAT';You can change it for your session with:
alter session set nls_date_format='<your_new_date_format>';Please take a look at:
http://download.oracle.com/docs/cd/B19306_01/server.102/b14237/initparams122.htm
http://download.oracle.com/docs/cd/B19306_01/server.102/b14200/sql_elements004.htm#sthref405
http://download.oracle.com/docs/cd/B19306_01/server.102/b14200/sql_elements003.htm#BABGIGCJ
The internal storage of a date-object does not depend on the actual value of NLS_DATE_FORMAT.
This will only used for output and for implicit conversions e.g. with to_date or to_char without explicit format.
To select a date from a table is also an implicit conversion to character, because you want to see characters on your screen.
Edited by: hm on 29.12.2010 04:20