Oracle: Limiting a join with a 'many' table to just one instance? - oracle

Question

This query returns a wide table containing horse-race results. However, one horse has multiple trainers and so this join is returning the same race-result for each trainer the horse has. How do I work around this? I've been playing around with Group By but Oracle doesn't seem to like it.
SELECT
b.meet_name AS Course,
a.race_time AS Time,
(f.jf_name||' '||f.jl_name) AS Jockey,
e.horse_name AS Horse,
c.odds,
d.place,
d.race_comment AS Note,
(g.bf_name||' '||g.bl_name) AS Breeder,
(h.tf_name||' '||h.tl_name) AS Trainer,
a.race_type AS Type,
a.distance AS Furlongs,
a.prize_money AS "Prize Money",
a.ground AS Ground
FROM proj_race_details a
JOIN proj_meet b ON a.meet_id = b.meet_id
JOIN proj_entry c ON c.race_id = a.race_id
JOIN proj_results d ON d.race_id = c.race_id AND d.horse_id = c.horse_id
JOIN proj_horses e ON e.horse_id = d.horse_id
JOIN proj_jockey f ON f.jockey_id = d.jockey_id
JOIN proj_breeder g ON g.breeder_id = e.breeder_id
JOIN proj_trainer h ON h.trainer_id = e.trainer_id;

Answer 1

EDIT:
This query would select only one trainer per horse. The trainer's name would be the first one, sorted alphabetically.
SELECT
b.meet_name AS Course,
a.race_time AS Time,
(f.jf_name||' '||f.jl_name) AS Jockey,
e.horse_name AS Horse,
c.odds,
d.place,
d.race_comment AS Note,
(g.bf_name||' '||g.bl_name) AS Breeder,
h.Trainer,
a.race_type AS Type,
a.distance AS Furlongs,
a.prize_money AS "Prize Money",
a.ground AS Ground
FROM proj_race_details a
JOIN proj_meet b ON a.meet_id = b.meet_id
JOIN proj_entry c ON c.race_id = a.race_id
JOIN proj_results d ON d.race_id = c.race_id AND d.horse_id = c.horse_id
JOIN proj_horses e ON e.horse_id = d.horse_id
JOIN proj_jockey f ON f.jockey_id = d.jockey_id
JOIN proj_breeder g ON g.breeder_id = e.breeder_id
JOIN
(SELECT ph.horse_id AS horse_id, MIN(pj.tf_name||' '||pj.tl_name) AS Trainer
FROM proj_trainer pj INNER JOIN proj_horses ph
ON pj.trainer_id = ph.trainer_id
GROUP BY ph.horse_id
) h
ON h.horse_id = e.horse_id;