Question

I’ve trawled the SO website thinking this is pretty obvious but alas I have not found one yet.
Basically the setup is as follows:

I have a string in a table like so:

06/22/2010 00:00:00

I do a select on it:

SELECT To_Date(item, 'MM/DD/YYYY HH24:MI:SS') from that_table

so that effectively I am doing

SELECT To_Date('06/22/2010 00:00:00', 'MM/DD/YYYY HH24:MI:SS') from that_table

My database returns:

22.06.2010 00:00:00

Now I know I can do a

to_char(to_Date('06/22/2010 00:00:00', 'MM/DD/YYYY HH24:MI:SS'), 'MM/DD/YYYY HH24:MI:SS')

but I need the select to return a date format (MM/DD/YYYY HH24:MI:SS), not a string. How can I do that?

Edit:
Real output:

22.06.2010 00:00:00

Desired output (in Date format):

06/22/2010 00:00:00

Answer 1

a Date is a point in time, it has no format (like numbers: they don’t have format). When you display the date, obviously it has to get a format: if you don’t specifically give Oracle a format, the default format for your session will be used (session parameter NLS_DATE_FORMAT).

In consequence: use the DATE datatype for date arithmetics and storage (no format). Use the to_char function or something equivalent when you need to display the date (in a report or in the GUI).