- [removed] The legacy "mutable" system of the

ORM, including the MutableType class as well
as the mutable=True flag on PickleType
and postgresql.ARRAY has been removed.
In-place mutations are detected by the ORM
using the sqlalchemy.ext.mutable extension,
introduced in 0.7.   The removal of MutableType
and associated constructs removes a great
deal of complexity from SQLAlchemy's internals.
The approach performed poorly as it would incur
a scan of the full contents of the Session
when in use. [ticket:2442]

1 files changed, 2 insertions, 13 deletions

diff --git a/lib/sqlalchemy/orm/identity.py b/lib/sqlalchemy/orm/identity.py
index 59d121de9..bb5fbb6e8 100644
--- a/lib/sqlalchemy/orm/identity.py
+++ b/lib/sqlalchemy/orm/identity.py
@@ -10,7 +10,6 @@ from sqlalchemy.orm import attributes
 
 class IdentityMap(dict):
     def __init__(self):
-        self._mutable_attrs = set()
         self._modified = set()
         self._wr = weakref.ref(self)
 
@@ -31,28 +30,18 @@ class IdentityMap(dict):
 
         if state.modified:
             self._modified.add(state)
-        if state.manager.mutable_attributes:
-            self._mutable_attrs.add(state)
 
     def _manage_removed_state(self, state):
         del state._instance_dict
-        self._mutable_attrs.discard(state)
         self._modified.discard(state)
 
     def _dirty_states(self):
-        return self._modified.union(s for s in self._mutable_attrs.copy()
-                                    if s.modified)
+        return self._modified
 
     def check_modified(self):
         """return True if any InstanceStates present have been marked as 'modified'."""
 
-        if self._modified:
-            return True
-        else:
-            for state in self._mutable_attrs.copy():
-                if state.modified:
-                    return True
-        return False
+        return bool(self._modified)
 
     def has_key(self, key):
         return key in self