select paper_id, task_id, num,counts, paper_score,roll_up, is_ab, status ,create_time,update_time,creator,updater ,deleted from education_paper SELECT q.*, a.answer_id, a.qu_id AS a_qu_id, a.is_right, a.image, a.content AS a_content, a.contentIn AS a_content_in, a.score_rate, a.sort AS a_sort, epq.sort AS question_sort FROM ( SELECT * FROM education_paper_qu WHERE paper_id = #{paperId} ORDER BY sort ASC ) epq JOIN exam_question q ON epq.qu_id = q.qu_id LEFT JOIN exam_question_answer a ON q.qu_id = a.qu_id ORDER BY epq.sort ASC, -- 保证题目顺序 CASE WHEN a.sort IS NOT NULL THEN 0 ELSE 1 END, a.sort ASC; -- 保证答案顺序