diff --git a/science_article_cnki/science_article_cnki/pipelines.py b/science_article_cnki/science_article_cnki/pipelines.py
index 715dc65..dc9a93a 100644
--- a/science_article_cnki/science_article_cnki/pipelines.py
+++ b/science_article_cnki/science_article_cnki/pipelines.py
@@ -41,6 +41,7 @@ class MongoPipeline(MongoDBUtils):
         super().__init__(mongo_uri, mongo_db)
         self.stats: StatsCollector = stats
         self.insert_failure_update_enable = True
+        self.duplicate_cover_enable = False  # 重复项覆盖
 
     @classmethod
     def from_crawler(cls, crawler: Crawler):
@@ -71,7 +72,8 @@ class MongoPipeline(MongoDBUtils):
                 logger.debug("dupKey: %s, keyValue: %s", key_pattern, key_value)
                 d.pop("_id", None)
                 [d.pop(k, None) for k in key_pattern.keys()]
-                up_result = collection.update_one(filter=key_value, update={"$set": d}, upsert=True)
+                update_q = build_update_query(d, replace=self.duplicate_cover_enable)
+                up_result = collection.update_one(filter=key_value, update=update_q, upsert=True)
                 self.stats.inc_value("item2db_updated/{}".format(item_type))
         except Exception:
             raise