diff --git a/chassis/db_model.py b/chassis/db_model.py
index 1be0e10..2cda20f 100644
--- a/chassis/db_model.py
+++ b/chassis/db_model.py
@@ -3,10 +3,13 @@ from sqlalchemy.ext.declarative import declarative_base
 from datetime import datetime
 
 BaseModel = declarative_base()
+metadata = BaseModel.metadata
 
 
 class BaseCrud(BaseModel):
 
+    __abstract__ = True
+
     # 硬删除
     def delete(self, session, commit=False):
         session.delete(self)
@@ -47,6 +50,8 @@ class BaseCrud(BaseModel):
 
 class InfoCrud(BaseModel):
 
+    __abstract__ = True
+
     create_time = Column(DateTime(), default=func.now())
     update_time = Column(DateTime(), default=func.now(), onupdate=func.now())
     delete_time = Column(DateTime())
diff --git a/setup.py b/setup.py
index c5e8f43..8e04e5b 100644
--- a/setup.py
+++ b/setup.py
@@ -60,6 +60,7 @@ setup(
         'rocketry': ['rocketry==2.4.0'],
         'gutter': ['gutter==0.5.0'],
         'mysql': ['pymysql==1.0.3',
-                  'sqlalchemy==2.0.15'],
+                  'sqlalchemy==2.0.15',
+                  'sqlacodegen==2.3.0'],
     },
 )