diff --git a/collection/opendb-mall-categories/collection.json b/collection/opendb-mall-categories/collection.json
index c7967b1..ad0fb04 100644
--- a/collection/opendb-mall-categories/collection.json
+++ b/collection/opendb-mall-categories/collection.json
@@ -6,6 +6,10 @@
       "_id": {
         "description": "存储文档 ID（文章 ID），系统自动生成"
       },
+      "parent_id": {
+        "bsonType": "string",
+        "description": "父ID，用于多级分类"
+      },
       "name": {
         "bsonType": "string",
         "description": "类别名称",