diff --git a/backend/common/core/sqlbot_cache.py b/backend/common/core/sqlbot_cache.py
index 15018019..dda597b1 100644
--- a/backend/common/core/sqlbot_cache.py
+++ b/backend/common/core/sqlbot_cache.py
@@ -37,6 +37,8 @@ def custom_key_builder(
             
             # 支持属性路径格式
             parts = keyExpression.split('.')
+            if not bound_args.arguments.get(parts[0]):
+                return f"{base_key}{parts[0]}"
             value = bound_args.arguments[parts[0]]
             for part in parts[1:]:
                 value = getattr(value, part)
diff --git a/backend/main.py b/backend/main.py
index 48e124f7..dddc3e89 100644
--- a/backend/main.py
+++ b/backend/main.py
@@ -51,6 +51,7 @@ async def lifespan(app: FastAPI):
     SQLBotLogUtil.info("✅ SQLBot 初始化完成")
     await sqlbot_xpack.core.clean_xpack_cache()
     await async_model_info()  # 异步加密已有模型的密钥和地址
+    await sqlbot_xpack.core.monitor_app(app)
     yield
     SQLBotLogUtil.info("SQLBot 应用关闭")