diff --git a/web-infrastructure/src/main/resources/mapper/study/StudentSignMapper.xml b/web-infrastructure/src/main/resources/mapper/study/StudentSignMapper.xml
index 7cbb41f..2887b51 100644
--- a/web-infrastructure/src/main/resources/mapper/study/StudentSignMapper.xml
+++ b/web-infrastructure/src/main/resources/mapper/study/StudentSignMapper.xml
@@ -99,10 +99,11 @@
             AND ss.delete_enum = 'FALSE'
             and ss.sign_url is not null
             and ss.sign_url != ''
-
+        </where>
+            GROUP BY ss.id
             order by
             ss.create_time desc
-        </where>
+
     </select>
 
     <!--<select id="listAllByStudentId" resultType="com.zcloud.edu.persistence.dataobject.study.StudentSignDO">-->