id , exam_paper_id, paper_name, paper_type, subject_id, system_score, user_score, paper_score, question_correct, question_count, do_time, status, create_user, create_time, task_exam_id SELECT FROM t_exam_paper_answer and create_user = #{createUser} and subject_id = #{subjectId} SELECT count(*) from t_exam_paper_answer SELECT create_time as name, COUNT(create_time) as value from ( SELECT DATE_FORMAT(create_time, '%Y-%m-%d') as create_time from t_exam_paper_answer WHERE create_time between #{startTime} and #{endTime} ) a GROUP BY create_time select from t_exam_paper_answer where exam_paper_id = #{pid} and create_user=#{uid} limit 1 SELECT FROM t_exam_paper_answer and subject_id = #{subjectId}