SELECT
    sport_name as "Sport Name",
    COUNT(discipline_code) as "Number of Disciplines"
FROM
    GAMES.SPORT,
    GAMES.GAMESDISCIPLINE,
    GAMES.SUMMERGAMES
WHERE
    sg_year = 2012
GROUP BY
    sport_name;

SELECT
    s.sport_name as "Sport Name",
    COUNT(gs.discipline_code) as "Number of Disciplines"
FROM GAMES.SUMMERGAMES sg
JOIN GAMES.GAMESDISCIPLINE gd ON gd.games_id = sg.games_id
JOIN GAMES.SPORT s ON s.discipline_id = gd.discipline_id
WHERE
    sg.sg_year = 2012
GROUP BY
    s.sport_name;