mysql – update – Update from select – example
UPDATE rs_users as a INNER JOIN (SELECT user_id, meta_value FROM wp_usermeta WHERE meta_key = 'telefon') as b ON a.user_id = b.user_id SET a.phone = b.meta_value
UPDATE rs_users as a INNER JOIN (SELECT user_id, meta_value FROM wp_usermeta WHERE meta_key = 'telefon') as b ON a.user_id = b.user_id SET a.phone = b.meta_value