Hi Sahil,
It depends on what you exactly want to do with the stored data.Ofcourse if its just storing the data and retrieving in the same application/format then u can opt for a database .
XML was designed basically to carry data.
If you need use the data in another application which might not recognise the existingformat / format of ur database then u need to manually do the transformation.To avoid this overhead xml is used in the scenario.Furthuremore , there are added advantages like ease in presentation/formatting using stylesheet languagesetc.....
Suggested link:
www. w3schools.com