diff --git a/gvsdsdk/model_base.py b/gvsdsdk/model_base.py
index 34b2d9f..9170247 100644
--- a/gvsdsdk/model_base.py
+++ b/gvsdsdk/model_base.py
@@ -352,14 +352,7 @@ class FieldExpressionDescriptor:
 
 class QModelBase(models.base.ModelBase):
     def __new__(mcs, name, bases, namespace, **kwargs):
-        from django.db import models as dj_models
-        for attr_name, attr_val in list(namespace.items()):
-            if isinstance(attr_val, dj_models.Field) and not attr_val.db_column:
-                # ForeignKey/OneToOneField 的数据库列名是 attr_name + '_id'
-                if isinstance(attr_val, (dj_models.ForeignKey, dj_models.OneToOneField)):
-                    attr_val.db_column = attr_name + '_id'
-                else:
-                    attr_val.db_column = attr_name
+        # 不再强制设置 db_column —— Django 会自动处理
 
         # 动态设置 managed：子服务器可设 GVSDSDK_MANAGE_TABLES=True 让 gvsdsdk 管理表
         meta = namespace.get('Meta')
@@ -373,40 +366,70 @@ class QModelBase(models.base.ModelBase):
 
         cls = super().__new__(mcs, name, bases, namespace, **kwargs)
 
-        # 模型创建后，自动为所有字段添加描述符，支持 Model.field_name 链式 OOP
+        # 模型创建后，包装字段描述符以支持类级别 FieldExpression
         if not cls._meta.abstract:
-            _attach_field_descriptors(cls)
+            _wrap_field_descriptors(cls)
 
         return cls
 
 
-def _attach_field_descriptors(cls: Type) -> None:
-    """为 QModel 子类的所有字段自动添加 FieldExpressionDescriptor / ForeignKeyIdDescriptor，
-    使 Model.field_name 在类级别访问时返回 FieldExpression，支持链式 OOP 查询。"""
-    from django.db import models as dj_models
+def _wrap_field_descriptors(cls: Type) -> None:
+    """包装 Django 字段描述符，使类级别访问返回 FieldExpression，
+    实例级别完全委托给 Django 原生描述符。
+
+    Django 的字段描述符（DeferredAttribute / ForwardManyToOneDescriptor）：
+    - __get__(None, cls) → 返回字段对象本身（类级别）
+    - __get__(instance, cls) → 返回字段值（实例级别）
+
+    我们包装后：
+    - __get__(None, cls) → 返回 FieldExpression（类级别，用于链式 OOP）
+    - __get__(instance, cls) → 委托给原生描述符（实例级别，正常行为）
+    """
+    from django.db.models.query_utils import DeferredAttribute
+    from django.db.models.fields.related_descriptors import (
+        ForwardManyToOneDescriptor,
+        ForwardOneToOneDescriptor,
+    )
 
     for field in cls._meta.local_fields:
         fname = field.name
-        # 跳过已有描述符或内部属性
         if fname.startswith('_'):
             continue
-        # 检查是否已有同名描述符（避免覆盖手动定义的）
-        existing = cls.__dict__.get(fname)
-        if isinstance(existing, (FieldExpressionDescriptor, ForeignKeyIdDescriptor)):
-            continue
-        # 跳过 Django 自动创建的反向关系和 id 主键（如果用户未显式定义）
-        if fname == 'id' and field.primary_key and not isinstance(
-            cls.__dict__.get(fname), (FieldExpressionDescriptor, ForeignKeyIdDescriptor)
-        ):
-            # id 字段也添加描述符
-            setattr(cls, fname, FieldExpressionDescriptor(fname))
+
+        original_desc = cls.__dict__.get(fname)
+        if original_desc is None:
             continue
 
-        if isinstance(field, (dj_models.ForeignKey, dj_models.OneToOneField)):
-            # FK 字段：类级别访问返回 FieldExpression，实例级别访问返回关联对象
-            setattr(cls, fname, ForeignKeyIdDescriptor(fname))
+        # 只包装已知的 Django 描述符类型
+        if isinstance(original_desc, (DeferredAttribute, ForwardManyToOneDescriptor,
+                                       ForwardOneToOneDescriptor)):
+            wrapper = _FieldExpressionWrapper(original_desc, cls, fname)
+            setattr(cls, fname, wrapper)
+
+
+class _FieldExpressionWrapper:
+    """包装 Django 字段描述符，类级别返回 FieldExpression，实例级别委托给原生描述符。"""
+
+    def __init__(self, original_descriptor, model_class, field_name):
+        self._original = original_descriptor
+        self._model = model_class
+        self._field_name = field_name
+        self._has_set = hasattr(original_descriptor, '__set__')
+
+    def __get__(self, obj, objtype=None):
+        if obj is None:
+            # 类级别访问：返回 FieldExpression
+            return FieldExpression(self._model, self._field_name)
+        # 实例级别访问：委托给原生 Django 描述符
+        return self._original.__get__(obj, objtype)
+
+    def __set__(self, obj, value):
+        if self._has_set:
+            # FK/O2O 描述符有 __set__
+            self._original.__set__(obj, value)
         else:
-            setattr(cls, fname, FieldExpressionDescriptor(fname))
+            # 普通字段（DeferredAttribute）没有 __set__，直接写 __dict__
+            obj.__dict__[self._field_name] = value
 
 
 class QModel(models.Model, metaclass=QModelBase):