diff --git a/pysqlsync/dialect/oracle/discovery.py b/pysqlsync/dialect/oracle/discovery.py
index 40d9972..3a7b8a4 100644
--- a/pysqlsync/dialect/oracle/discovery.py
+++ b/pysqlsync/dialect/oracle/discovery.py
@@ -232,8 +232,6 @@ async def _get_namespace(self, namespace_id: Optional[LocalId] = None) -> Namesp
             tables.append(table)
 
         if tables:
-            return self.factory.namespace_class(
-                LocalId(""), enums=[], structs=[], tables=tables
-            )
+            return self.factory.namespace_class(enums=[], structs=[], tables=tables)
         else:
             return self.factory.namespace_class()
diff --git a/pysqlsync/dialect/postgresql/discovery.py b/pysqlsync/dialect/postgresql/discovery.py
index 0012dbf..912fc63 100644
--- a/pysqlsync/dialect/postgresql/discovery.py
+++ b/pysqlsync/dialect/postgresql/discovery.py
@@ -392,7 +392,7 @@ async def get_namespace(self, namespace_id: LocalId) -> Namespace:
             table = await self.get_table(QualifiedId(namespace_id.id, table_name))
             tables.append(table)
 
-        if tables:
+        if enums or structs or tables:
             return self.factory.namespace_class(
                 namespace_id, enums=enums, structs=structs, tables=tables
             )
diff --git a/pysqlsync/formation/object_types.py b/pysqlsync/formation/object_types.py
index 3469596..3753161 100644
--- a/pysqlsync/formation/object_types.py
+++ b/pysqlsync/formation/object_types.py
@@ -534,6 +534,16 @@ def __init__(self) -> None:
     def __init__(self, name: LocalId) -> None:
         ...
 
+    @overload
+    def __init__(
+        self,
+        *,
+        enums: list[EnumType],
+        structs: list[StructType],
+        tables: list[Table],
+    ) -> None:
+        ...
+
     @overload
     def __init__(
         self,