id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	round	ref	PRIMARY,idx-round-tournament_id	idx-round-tournament_id	4	const	3	Using index; Using temporary; Using filesort
1	SIMPLE	match	ref	idx-match-round_id	idx-match-round_id	4	bsr.round.round_id	3	NULL