Convert lazy loader, selectinload, load_on_ident to lambda statements

Building on newly robust lambdas in
I29a513c98917b1d503abfdd61e6b6e8800851aa8,
convert key loading off of the "baked" system so that baked
is no longer used by the ORM.

Change-Id: I3abfb45dd6e50f84f29d39434caa0b550ce27864

1 files changed, 13 insertions, 3 deletions

diff --git a/lib/sqlalchemy/orm/mapper.py b/lib/sqlalchemy/orm/mapper.py
index 2b04f1cc7..6d22c6205 100644
--- a/lib/sqlalchemy/orm/mapper.py
+++ b/lib/sqlalchemy/orm/mapper.py
@@ -719,9 +719,8 @@ class Mapper(
         """
         return self
 
-    _cache_key_traversal = [
-        ("mapper", visitors.ExtendedInternalTraversal.dp_plain_obj),
-    ]
+    def _gen_cache_key(self, anon_map, bindparams):
+        return (self,)
 
     @property
     def entity(self):
@@ -2315,6 +2314,17 @@ class Mapper(
             )
         )
 
+    @property
+    def _all_column_expressions(self):
+        poly_properties = self._polymorphic_properties
+        adapter = self._polymorphic_adapter
+
+        return [
+            adapter.columns[prop.columns[0]] if adapter else prop.columns[0]
+            for prop in poly_properties
+            if isinstance(prop, properties.ColumnProperty)
+        ]
+
     def _columns_plus_keys(self, polymorphic_mappers=()):
         if polymorphic_mappers:
             poly_properties = self._iterate_polymorphic_properties(