Inventory pulling for user accounts question

I have an Inventory set up in a database and then I have user accounts. The Inventory database I would like to keep as the master, as in this is all the possible items you can have. Then I would like the user when logedin to beable to update what items they have of the inventory without changing the main inventory list.

So my question is, do I create a sepreate database for each person that calls on the main inventory database and each user have there own database, or is there a more simple way to do that?

I am using mysql with Phpadmin, if you need to know that.

No you just need to keep the last item a user got, and then give them the new ones

Oh, well, that seems simple enough. Thanks you rock.

Yeah I do. I listen rock for more than 20 years :) (just kidding)