PRIMARY KEY (song, machine, playmode, difficulty)
);
+CREATE INDEX songratings_feetrating ON songratings ( feetrating );
CREATE TABLE players (
player SERIAL PRIMARY KEY,
tournament INTEGER NOT NULL REFERENCES bigscreen.active_tournament,
round INTEGER NOT NULL,
parallel INTEGER NOT NULL,
+ num_machines INTEGER NOT NULL,
last_updated TIMESTAMP NOT NULL,
PRIMARY KEY ( tournament, round, parallel ),