- [feature] The Query can now load entity/scalar-mixed

    "tuple" rows that contain
    types which aren't hashable, by setting the flag
    "hashable=False" on the corresponding TypeEngine object
    in use.  Custom types that return unhashable types
    (typically lists) can set this flag to False.
    [ticket:2592]
  - [bug] Applying a column expression to a select
    statement using a label with or without other
    modifying constructs will no longer "target" that
    expression to the underlying Column; this affects
    ORM operations that rely upon Column targeting
    in order to retrieve results.  That is, a query
    like query(User.id, User.id.label('foo')) will now
    track the value of each "User.id" expression separately
    instead of munging them together.  It is not expected
    that any users will be impacted by this; however,
    a usage that uses select() in conjunction with
    query.from_statement() and attempts to load fully
    composed ORM entities may not function as expected
    if the select() named Column objects with arbitrary
    .label() names, as these will no longer target to
    the Column objects mapped by that entity.
    [ticket:2591]

1 files changed, 11 insertions, 3 deletions

diff --git a/lib/sqlalchemy/orm/query.py b/lib/sqlalchemy/orm/query.py
index 35d32651f..a6d20a973 100644
--- a/lib/sqlalchemy/orm/query.py
+++ b/lib/sqlalchemy/orm/query.py
@@ -29,7 +29,8 @@ from .util import (
     _is_aliased_class, _is_mapped_class, _orm_columns,
     join as orm_join,with_parent, aliased
     )
-from .. import sql, util, log, exc as sa_exc, inspect, inspection
+from .. import sql, util, log, exc as sa_exc, inspect, inspection, \
+        types as sqltypes
 from ..sql.expression import _interpret_as_from
 from ..sql import (
         util as sql_util,
@@ -2930,12 +2931,20 @@ class _ColumnEntity(_QueryEntity):
             if c is not column:
                 return
 
+
         if not isinstance(column, sql.ColumnElement):
             raise sa_exc.InvalidRequestError(
                 "SQL expression, column, or mapped entity "
                 "expected - got '%r'" % (column, )
             )
 
+        type_ = column.type
+        if type_.hashable:
+            self.filter_fn = lambda item: item
+        else:
+            counter = util.counter()
+            self.filter_fn = lambda item: counter()
+
         # If the Column is unnamed, give it a
         # label() so that mutable column expressions
         # can be located in the result even
@@ -2972,6 +2981,7 @@ class _ColumnEntity(_QueryEntity):
         else:
             self.entity_zero = None
 
+
     @property
     def entity_zero_or_selectable(self):
         if self.entity_zero is not None:
@@ -2985,8 +2995,6 @@ class _ColumnEntity(_QueryEntity):
     def type(self):
         return self.column.type
 
-    def filter_fn(self, item):
-        return item
 
     def adapt_to_selectable(self, query, sel):
         c = _ColumnEntity(query, sel.corresponding_column(self.column))