Is null

jeecg-module-system/jeecg-system-biz/src/main/java/org/jeecg/modules/adweb/seo/mapper/xml/SeoKeywordsMapper.xml

@@ -177,7 +177,7 @@
         <if test="keywordType != null">
             AND keyword_type = #{keywordType}
         </if>
-        AND last_search_time <![CDATA[ <]]> CURDATE()
+        AND (last_search_time <![CDATA[ <]]> CURDATE() OR last_search_time IS NULL)
         LIMIT #{limit}
     </select>