课表列表获取上课时长，剔除考勤为空的数据

mec-biz/src/main/resources/config/mybatis/TeacherAttendanceMapper.xml

@@ -598,6 +598,8 @@
         FROM teacher_attendance ta
         LEFT JOIN student_attendance sa ON ta.course_schedule_id_ = sa.course_schedule_id_
         WHERE ta.course_schedule_id_ = #{courseScheduleId}
+        AND ta.sign_in_time_ IS NOT NULL AND ta.sign_out_time_ IS NOT NULL
+        AND sa.sign_in_time_ IS NOT NULL AND sa.sign_out_time_ IS NOT NULL
     </select>
     <select id="findFirstSign" resultType="java.lang.Long">
         SELECT ta.course_schedule_id_ FROM teacher_attendance ta