update

examcloud-core-questions-service/src/main/java/cn/com/qmth/examcloud/core/questions/service/PaperStructService.java

@@ -525,7 +525,7 @@ public class PaperStructService {
 
         // 从数据库中获取
         Query query = new Query();
-        query.addCriteria(Criteria.where("id").is(new ObjectId(paperStructId)));
+        query.addCriteria(Criteria.where("_id").is(new ObjectId(paperStructId)));
         ps = this.mongoTemplate.findOne(query, PaperStructCache.class);
         if (ps == null) {
             throw new StatusException("未找到试卷结构:" + paperStructId);