fix: avoid checking variables with empty value (#5367)

fix: enhance load_from_db field checks in custom component update and parameter loading

- Updated the condition in  to ensure that  only includes fields with a defined value.
- Modified the  function to skip parameters that are either not present or have a falsy value, improving robustness in parameter handling.

src/backend/base/langflow/api/v1/endpoints.py

@@ -622,7 +622,7 @@ async def custom_component_update(
             load_from_db_fields = [
                 field_name
                 for field_name, field_dict in template.items()
-                if isinstance(field_dict, dict) and field_dict.get("load_from_db")
+                if isinstance(field_dict, dict) and field_dict.get("load_from_db") and field_dict.get("value")
             ]
             params = await update_params_with_load_from_db_fields(cc_instance, params, load_from_db_fields)
             cc_instance.set_attributes(params)

src/backend/base/langflow/interface/initialize/loading.py

@@ -111,7 +111,7 @@ async def update_params_with_load_from_db_fields(
     fallback_to_env_vars=False,
 ):
     for field in load_from_db_fields:
-        if field not in params:
+        if field not in params or not params[field]:
             continue
 
         try: