INSERT INTO t_subject_dept(subject_id, dept_id) VALUES (#{item.subjectId}, #{item.deptId}) DELETE FROM t_subject_dept WHERE subject_id = #{subjectId} SELECT tdq.dept_id, td.name as deptName FROM t_subject_dept tdq INNER JOIN t_department td ON td.id = tdq.dept_id WHERE tdq.subject_id = #{subjectId}