@odeddror I'm not sure I understand your question fully.. The calculated column MgrPath = PATH([user_id],[user_mgr]) is set in the USERS_REVERE table. It uses two columns that come from a sql query, user_id and user_mgr. the PATH function creates a | delimited string showing that user's managerial hierarchy.
Then the VLOOKUP and PATHCONTAINS functions simply looks for the current logged in users name in that string. If their name appears then any data related to that record will show for the user.