express the check for 'filter' in terms of _MapperEntity being present or not.

move away slightly from the _mapper_entities collection.

diff --git a/lib/sqlalchemy/orm/query.py b/lib/sqlalchemy/orm/query.py
index 54e864abb11232dd6557b392b9d0f1749c940772..98f9885a360ae1c68643d4557aca3d87ef9c8f82 100644 (file)
--- a/lib/sqlalchemy/orm/query.py
+++ b/lib/sqlalchemy/orm/query.py
@@ -1866,7 +1866,13 @@ class Query(object):
 
         context.runid = _new_runid()
 
-        filtered = bool(list(self._mapper_entities))
+        for ent in self._entities:
+            if isinstance(ent, _MapperEntity):
+                filtered = True
+                break
+        else:
+            filtered = False
+
         single_entity = filtered and len(self._entities) == 1
 
         if filtered: