sql优化

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

@@ -3716,7 +3716,7 @@
         <foreach collection="classGroupIds" open="(" close=")" separator="," item="item">
             #{item}
         </foreach>
-        AND merge_flag_ IN (1,2) IS NOT NULL AND pre_course_flag_ = 0
+        AND merge_flag_ IN (1,2) AND pre_course_flag_ = 0
         AND status_ = 'NOT_START'
     </select>
     <select id="getLock" resultMap="CourseSchedule">