SELECT *, (SELECT COUNT(1) FROM user_binding_teacher WHERE teacher_id_=#{teacherId}) AS studentCount FROM piano_room_time WHERE teacher_id_=#{teacherId} SELECT COUNT(1) FROM user_binding_teacher WHERE teacher_id_=#{teacherId} UPDATE user_binding_teacher SET last_end_class_ = #{item.endTime} WHERE teacher_id_ = #{item.teacherId} AND student_id_ = #{item.studentId} UPDATE piano_room_time SET frozen_time_ = #{item.frozenTime} WHERE teacher_id_ = #{item.teacherId}