SELECT
    COUNT(events.event_id) AS total_events,
    COUNT(matches.fight_id) AS total_matches,
    COUNT(players.fighter_id) AS total_players,
    COUNT(DISTINCT events.organization) AS total_organizations,
    COUNT(DISTINCT players.country) AS total_countries
FROM
    events, matches, players

SELECT
    COUNT(events.event_id) AS total_events,
    COUNT(DISTINCT events.organization) AS total_organizations
FROM
    events;

SELECT
    COUNT(matches.fight_id) AS total_matches
FROM
    matches;

SELECT
    COUNT(players.fighter_id) AS total_players,
    COUNT(DISTINCT players.country) AS total_countries
FROM
    players;

CREATE INDEX "events_organization" ON events (organization);
CREATE INDEX "players_country" ON events (country);