- Improved the determination of the FROM clause

when placing SQL expressions in the query()
list of entities.  In particular scalar subqueries
should not "leak" their inner FROM objects out
into the enclosing query.

diff --git a/CHANGES b/CHANGES
index 1a911122b707c680829c9862cf55da432fe1142c..a5258ceacffd04cea161dd3db5bb52d1c35a465b 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -16,6 +16,12 @@ CHANGES
       Column objects such as Query(table.c.col) will
       return the "key" attribute of the Column.
 
+    - Improved the determination of the FROM clause
+      when placing SQL expressions in the query()
+      list of entities.  In particular scalar subqueries
+      should not "leak" their inner FROM objects out
+      into the enclosing query.
+      
 - sql
     - Temporarily rolled back the "ORDER BY" enhancement
       from [ticket:1068].  This feature is on hold 

diff --git a/lib/sqlalchemy/orm/query.py b/lib/sqlalchemy/orm/query.py
index 43dde9fc053bdd3841e0408bea0faa3251679640..b5250638649bc13650978ab441e470c2146311c8 100644 (file)
--- a/lib/sqlalchemy/orm/query.py
+++ b/lib/sqlalchemy/orm/query.py
@@ -1625,11 +1625,22 @@ class _ColumnEntity(_QueryEntity):
 
         self.column = column
         self.froms = set()
+        
+        # look for ORM entities represented within the
+        # given expression.  Try to count only entities 
+        # for columns whos FROM object is in the actual list
+        # of FROMs for the overall expression - this helps
+        # subqueries which were built from ORM constructs from
+        # leaking out their entities into the main select construct
+        actual_froms = set(column._get_from_objects())
+
         self.entities = util.OrderedSet(
             elem._annotations['parententity']
             for elem in visitors.iterate(column, {})
-            if 'parententity' in elem._annotations)
-        
+            if 'parententity' in elem._annotations
+            and actual_froms.intersection(elem._get_from_objects())
+            )
+            
         if self.entities:
             self.entity_zero = list(self.entities)[0]
         else:

diff --git a/test/orm/inheritance/query.py b/test/orm/inheritance/query.py
index 0ce3b4fb78a305e441a7216de2004303134ec9aa..28659ba38a3e4c71c8fc4ae459e653a38424f2f3 100644 (file)
--- a/test/orm/inheritance/query.py
+++ b/test/orm/inheritance/query.py
@@ -510,7 +510,6 @@ def make_test(select_type):
             
             self.assertEquals(sess.query(Person).filter(Person.person_id==subq).one(), e1)
             
-        
         def test_mixed_entities(self):
             sess = create_session()
 
@@ -537,7 +536,6 @@ def make_test(select_type):
                 [('pointy haired boss foo', ), ('dogbert foo',)]
             )
 
-
             row = sess.query(Engineer.name, Engineer.primary_language).filter(Engineer.name=='dilbert').first()
             assert row.name == 'dilbert'
             assert row.primary_language == 'java'

diff --git a/test/orm/query.py b/test/orm/query.py
index 30cb03ab86c1fc97f0cb7bb8d56ad7f3586be6cf..d3e69573ddf0fe74d83925f386243a84c69c0143 100644 (file)
--- a/test/orm/query.py
+++ b/test/orm/query.py
@@ -1207,6 +1207,36 @@ class MixedEntitiesTest(QueryTest):
         q2 = q.select_from(sel).filter(users.c.id==8).filter(users.c.id>sel.c.id).values(users.c.name, sel.c.name, User.name)
         self.assertEquals(list(q2), [(u'ed', u'jack', u'jack')])
     
+    def test_scalar_subquery(self):
+        """test that a subquery constructed from ORM attributes doesn't leak out 
+        those entities to the outermost query.
+        
+        """
+        sess = create_session()
+        
+        subq = select([func.count()]).\
+            where(User.id==Address.user_id).\
+            correlate(users).\
+            label('count')
+
+        # we don't want Address to be outside of the subquery here
+        self.assertEquals(
+            list(sess.query(User, subq)[0:3]),
+            [(User(id=7,name=u'jack'), 1), (User(id=8,name=u'ed'), 3), (User(id=9,name=u'fred'), 1)]
+            )
+
+        # same thing without the correlate, as it should
+        # not be needed
+        subq = select([func.count()]).\
+            where(User.id==Address.user_id).\
+            label('count')
+
+        # we don't want Address to be outside of the subquery here
+        self.assertEquals(
+            list(sess.query(User, subq)[0:3]),
+            [(User(id=7,name=u'jack'), 1), (User(id=8,name=u'ed'), 3), (User(id=9,name=u'fred'), 1)]
+            )
+    
     def test_tuple_labeling(self):
         sess = create_session()
         for row in sess.query(User, Address).join(User.addresses).all():