submit

zhongzheng-system/src/main/resources/mapper/modules/grade/ClassGradeMapper.xml

@@ -936,7 +936,7 @@ PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
 
     <select id="getClassUserNumByTenant" parameterType="java.lang.Long" resultType="java.lang.Long">
         SELECT
-            sum( a.num )
+            IFNULL(sum( a.num ),0)
         FROM
             ( SELECT COUNT( user_id ) AS num FROM class_grade_user WHERE grade_id = #{gradeId} AND `status` = 1 AND change_grade = 0 GROUP BY user_id ) a
     </select>