My Rights table has the following structure:

RightKey    CategoryKey RoleKey     UserKey     RightName        RightCode          AllowDeny
----------- ----------- ----------- ----------- ---------------- ------------------ -----------
1           1           NULL        NULL        Add User         sys_add_user       1
2           1           NULL        NULL        Edit User        sys_edit_user      1
3           1           NULL        NULL        Remove User      sys_remove_user    1
4           1           NULL        NULL        Lock User        sys_lock_user      1
5           1           2           NULL        Add User         sys_add_user       1
6           1           2           NULL        Edit User        sys_edit_user      1
7           1           2           NULL        Remove User      sys_remove_user    1
8           1           2           NULL        Lock User        sys_lock_user      1
9           1           2              3           Remove User      sys_remove_user    0

The rows with NULL in RoleKey and UserKey are default rights assigned to new roles. When a user assigned to a role, he/she
gets all rights assigned to the role, as in RoleKey 2. Finally, individual user rights can be assigned, as in user 3 on row 9.


I'm trying to pull the rights for a user, but as you can see, the Remove User row is appearing twice. The result set should overwrite
the Role level rows with User level rows.

Here's what I have:

SELECT	rt.RightKey, rt.CategoryKey, rc.CategoryName, 
		rt.RoleKey, rt.UserKey, rt.RightName, rt.RightCode, rt.AllowDeny
	FROM sec_Rights rt
	LEFT JOIN sec_RightCategories rc ON rc.CategoryKey = rt.CategoryKey
	WHERE (rt.UserKey = @UserKey OR 
			rt.RoleKey = 
				(SELECT RoleKey
					FROM sec_Users
					WHERE UserKey = @UserKey))