selection.sql

SELECT * FROM (
  (SELECT people.id AS person_id, people.email AS person_email, people.name AS person_name, results.title AS result_title, results.id AS result_id
  FROM people, contents AS results, downloads
  WHERE results.id = 166674
  AND downloads.content_id = results.competition_id
  AND downloads.person_id = people.id)
  UNION
  (SELECT people.id AS person_id, people.email AS person_email, people.name AS person_name, results.title AS result_title, results.id AS result_id
  FROM people, contents AS results, resource_visits
  WHERE results.id = 166674
  AND resource_visits.competition_id = results.competition_id
  AND resource_visits.person_id = people.id)
) AS email