题库BUG查询

twzd-service/src/main/resources/mapper/qustion/QuestionInfoMapper.xml

@@ -88,7 +88,7 @@ PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
         </where>
 
         <if test="isRand!=null and isRand!=''"> order by rand() </if>
-        <if test="isRand==null or isRand=='' and  sort!=null and sort!='' "> order by ${sort} </if>
+        <if test="isRand==null or isRand=='' and  sort!=null and sort!='' "> order by IFNULL(${sort},'a') </if>
     </select>