Hi Mahtab,
There is no default format string for date and for timestamp. It is dependent on the location settings.
Your date, that might look as 21-OCT-2014 for you, will show 21-OKT-2014 for me.
Have a look at oracle's NLS documentation to see how language and country settings can influence date and number formats.
OCUP UML fundamental and ITIL foundation
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