id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	department	NULL	ref	department_confirmStatusIndex	department_confirmStatusIndex	2	const	1	10.00	Using where
1	SIMPLE	college	NULL	eq_ref	PRIMARY	PRIMARY	4	portal.department.collegeId	1	100.00	Using index
1	SIMPLE	college_info	NULL	ref	college_info_college_fk	college_info_college_fk	4	portal.college.id	1	100.00	Using where