insert into exam_user (`paper_id`,`user_id`,`role`) values (#{paperId},#{userId},#{role}) insert ignore into exam_user (`paper_id`,`user_id`,`role`) values (#{item.paperId},#{item.userId},#{item.role}) select * from exam_user where paper_id=#{paperId} select * from exam_user where user_id=#{userId} limit 1 select * from exam_user where paper_id=#{paperId} and user_id=#{userId}