Identify the user who has been yelping since 2004. Is he or she an Yelp Elite member?
has been yelping since 2004 refers to user_yelping_since_year = 2004
SELECT DISTINCT T2.user_id FROM Users AS T1 INNER JOIN Elite AS T2 ON T1.user_id = T2.user_id WHERE T1.user_yelping_since_year = 2004