How to declare return type for a function returning several rows and columns?

Hello,

I'm trying to create the following function which gives me
a runtime error, because it obviously doesn't return a mere
integer but several rows and columns (result of a join):

# create or replace function pref_daily_misere() returns setof integer as $BODY$
begin
create temporary table temp_ids (id varchar not null) on
commit drop;
insert into temp_ids (id)
select id
from pref_money
where yw = to_char(current_timestamp - interval '1
week', 'IYYY-IW')
order by money
desc limit 10;
create temporary table temp_rids (rid integer not null) on
commit drop;
insert into temp_rids (rid)
select rid
from pref_cards
where id in (select id from temp_ids) and
bid = 'Мизер' and
trix > 0;
-- return query select rid from temp_rids;

return query SELECT r.rid, r.cards, to_char(r.stamp,
'DD.MM.YYYY HH24:MI') as day,
c2.bid, c2.trix, c2.pos, c2.money, c2.last_ip, c2.quit,
u.id, u.first_name, u.avatar, u.female, u.city,
u.vip > CURRENT_DATE as vip
FROM pref_rounds r
JOIN pref_cards c1 USING (rid)
JOIN pref_cards c2 USING (rid)
JOIN pref_users u ON u.id = c2.id
WHERE r.rid in (select rid from temp_rids) order
by rid, pos;
return;
end;
$BODY$ language plpgsql;

The runtime error in PostgreSQL 8.4.11 is:

# select pref_daily_misere();
ERROR: structure of query does not match function result type
DETAIL: Number of returned columns (15) does not match expected
column count (1).
CONTEXT: PL/pgSQL function "pref_daily_misere" line 18 at RETURN QUERY

Does anybody please have an advice here?

The background: I have a table holding card game rounds:

# \d pref_rounds;
Table "public.pref_rounds"
Column | Type | Modifiers
--------+-----------------------------+-----------------------------------------------------------
rid | integer | not null default
nextval('pref_rounds_rid_seq'::regclass)
cards | text |
stamp | timestamp without time zone | default now()
Indexes:
"pref_rounds_pkey" PRIMARY KEY, btree (rid)
Referenced by:
TABLE "pref_cards" CONSTRAINT "pref_cards_rid_fkey" FOREIGN KEY
(rid) REFERENCES pref_rounds(rid) ON DELETE CASCADE

Each round is played by 3 players:

# \d pref_cards;
Table "public.pref_cards"
Column | Type | Modifiers
---------+-----------------------------+---------------
rid | integer |
id | character varying(32) |
bid | character varying(32) | not null
trix | integer | not null
pos | integer | not null
money | integer | not null
last_ip | inet |
quit | boolean |
stamp | timestamp without time zone | default now()
Indexes:
"pref_cards_id_index" btree (id)
"pref_cards_rid_index" btree (rid)
Foreign-key constraints:
"pref_cards_id_fkey" FOREIGN KEY (id) REFERENCES pref_users(id) ON
DELETE CASCADE
"pref_cards_rid_fkey" FOREIGN KEY (rid) REFERENCES
pref_rounds(rid) ON DELETE CASCADE

I'm trying to take the top 10 players of the last week,
so that I can display their certain bids for analyse on
a web page (similar to the table in the middle of
http://preferans.de/user.php?id=OK471018960997 )

Thank you
Alex