text: /* interactive-complex-1-a */
  select p2.id, p2.p_lastname, p2.p_birthday, p2.p_creationdate, p2.p_gender, p2.p_browserused, p2.p_locationip, pl.pl_name
  from
       person p1 JOIN (
           knows JOIN (
               person p2 JOIN place pl ON p2.p_placeid=pl.pl_placeid)
           ON k_person2id=p2.p_personid)
       ON p1.p_personid=k_person1id
  where p1.id = 21990232569319 and p2.p_firstname = 'John'
  ;