current_user, user_name(), system_user

Hi,

I am trying to identify what is the user/login that I am logged into the database when I use windows authentication.

I tried checking for user_name(), current_user and system_user values, as suggested in the archives. Two of them (user_name() and current_user) show me 'dbo' and system_user shows me the actual windows login.
But this windows login is not a valid database user. But still I am able to access database objects that are accessible to dbo. Please clarify.
Thanks
Raj

If the Windows Account you are logged in as is a member of a trusted Windows domain group with dbo rights, and your login is not explicitly denied (revoked) access to something, I believe it will allow you to see whatever the dbo can see.