How to store data with dynamic number of attributes in a database

Question

I have a number of different objects with a varying number of attributes. Until now I have saved the data in XML files which easily allow for an ever changing number of attr

Answer 1

if you are going to edit/manipulate/delete the attributes in later point, making a true n:m (second option) will be the one which I go for. (Or try to make it 2 table where the same attribute repeats.But data size will be high)

If you are not dealing with attributes(just capturing and showing the data) then you can go ahead and store in one field with some separator(Make sure the separator wont occur in the attribute value)