Get the persons, who are in both sets

Question

I have a question I don't know how to ask right, so I start with the SQL Statement (Postgres):

SELECT pc.person_id
  FROM groups g
  LEFT OUTER JOIN group_clubs gc ON (gc.group_id = g.id)
  LEFT OUTER JOIN person_club pc ON (gc.club_id = pc.club_id)
 WHERE g.id = 2

What I have: A group, which has a criteria with club, a user has to be in. This is split up into the groups table, the group_clubs table and the person_club table

What I want: I want to get all persons, who are in ALL the clubs, connected to this group. What I get: I get all the persons, who are in at least one of the clubs.

I am stuck and got no idea, how to get the result, only I need to intersect the results, but I don't know how to do it now...?!?

EDIT: To explain what I am looking for, here is a statement which does the same:

SELECT pc.person_id
  FROM person_club pc
 WHERE pc.club_id IN (
    SELECT gc.club_id
      FROM group_clubs gc
      WHERE gc.group_id = 2
 );

What I want is:

SELECT pc.person_id
  FROM person_club pc
 WHERE pc.club_id IN ALL(
     SELECT gc.club_id
       FROM group_clubs gc
      WHERE gc.group_id = 2
);

The person should be IN ALL of the group_clubs listed by this statement!

Answer 1

I got the answer thanks to a colleague:

SELECT pc.person_id
  FROM person_club_data pc
  INNER JOIN group_clubs gc ON (gc.club_id = pc.club_id)
 WHERE gc.group_id = 2
 GROUP BY pc.person_id
 HAVING COUNT(pc.person_id) >= (
     SELECT COUNT(gc.club_id)
       FROM group_clubs gc2
      WHERE gc2.group_id = 2
 )

I select the persons, and the persons who occur exactly as often as group_clubs rows can be found for group 2 and who are connected to this group.

Answer 2

Try this:

SELECT pc.person_id
  FROM groups g
  INNER JOIN group_clubs gc ON (gc.group_id = g.id)
  INNER JOIN person_club pc ON (gc.club_id = pc.club_id)
 WHERE g.id = 2

I don't think you need the last line (the WHERE clause) unless you meant to just retrieve one person.