- re-merge + CHANGES

AUTHORS

@@ -5,6 +5,7 @@ Major contributing authors include:
 - Michael Bayer <[email protected]>
 - Jason Kirtland <[email protected]>
 - Gaetan de Menten <[email protected]>
+- Diana Clarke <[email protected]>
 - Michael Trier <[email protected]>
 - Philip Jenvey <[email protected]>
 - Ants Aasma <[email protected]>

CHANGES

@@ -29,6 +29,15 @@ those which apply to an 0.7 release are noted.
     approach can be upgraded to this new 
     approach. [ticket:1401]
 
+  - [feature] Query now "auto correlates" by 
+    default in the same way as select() does.
+    Previously, a Query used as a subquery
+    in another would require the correlate()
+    method be called explicitly in order to 
+    correlate a table on the inside to the
+    outside.  As always, correlate(None)
+    disables correlation.  [ticket:2179]
+
   - [feature] Added prefix_with() method
     to Query, calls upon select().prefix_with()
     to allow placement of MySQL SELECT

lib/sqlalchemy/orm/query.py

@@ -2907,7 +2907,6 @@ def _compile_context(self, labels=True):
                         context.whereclause,
                         from_obj=froms,
                         use_labels=labels,
-                        correlate=False,
                         # TODO: this order_by is only needed if 
                         # LIMIT/OFFSET is present in self._select_args,
                         # else the application on the outside is enough
@@ -2973,7 +2972,6 @@ def _compile_context(self, labels=True):
                             from_obj=froms,
                             use_labels=labels,
                             for_update=for_update,
-                            correlate=False,
                             order_by=context.order_by,
                             **self._select_args
                         )

lib/sqlalchemy/orm/strategies.py

@@ -749,7 +749,7 @@ def _generate_from_original_query(self,
     ):
         # reformat the original query
         # to look only for significant columns
-        q = orig_query._clone()
+        q = orig_query._clone().correlate(None)
 
         # TODO: why does polymporphic etc. require hardcoding 
         # into _adapt_col_list ?  Does query.add_columns(...) work

test/orm/test_froms.py

@@ -66,6 +66,85 @@ def setup_mappers(cls):
         configure_mappers()
 
 
+class QueryCorrelatesLikeSelect(QueryTest, AssertsCompiledSQL):
+
+    query_correlated = "SELECT users.name AS users_name, " \
+        "(SELECT count(addresses.id) AS count_1 FROM addresses " \
+        "WHERE addresses.user_id = users.id) AS anon_1 FROM users"
+
+    query_not_correlated = "SELECT users.name AS users_name, " \
+        "(SELECT count(addresses.id) AS count_1 FROM addresses, users " \
+        "WHERE addresses.user_id = users.id) AS anon_1 FROM users"
+
+    def test_as_scalar_select_auto_correlate(self):
+        addresses, users = self.tables.addresses, self.tables.users
+        query = select(
+            [func.count(addresses.c.id)], 
+            addresses.c.user_id==users.c.id
+        ).as_scalar()
+        query = select([users.c.name.label('users_name'), query])
+        self.assert_compile(query, self.query_correlated,
+            dialect=default.DefaultDialect()
+        )
+
+    def test_as_scalar_select_explicit_correlate(self):
+        addresses, users = self.tables.addresses, self.tables.users
+        query = select(
+            [func.count(addresses.c.id)], 
+            addresses.c.user_id==users.c.id
+        ).correlate(users).as_scalar()
+        query = select([users.c.name.label('users_name'), query])
+        self.assert_compile(query, self.query_correlated,
+            dialect=default.DefaultDialect()
+        )
+
+    def test_as_scalar_select_correlate_off(self):
+        addresses, users = self.tables.addresses, self.tables.users
+        query = select(
+            [func.count(addresses.c.id)], 
+            addresses.c.user_id==users.c.id
+        ).correlate(None).as_scalar()
+        query = select([ users.c.name.label('users_name'), query])
+        self.assert_compile(query, self.query_not_correlated,
+            dialect=default.DefaultDialect()
+        )
+
+    def test_as_scalar_query_auto_correlate(self):
+        sess = create_session()
+        Address, User = self.classes.Address, self.classes.User
+        query = sess.query(func.count(Address.id))\
+            .filter(Address.user_id==User.id)\
+            .as_scalar()
+        query = sess.query(User.name, query)
+        self.assert_compile(query, self.query_correlated,
+            dialect=default.DefaultDialect()
+        )
+
+    def test_as_scalar_query_explicit_correlate(self):
+        sess = create_session()
+        Address, User = self.classes.Address, self.classes.User
+        query = sess.query(func.count(Address.id))\
+            .filter(Address.user_id==User.id)\
+            .correlate(self.tables.users)\
+            .as_scalar()
+        query = sess.query(User.name, query)
+        self.assert_compile(query, self.query_correlated,
+            dialect=default.DefaultDialect()
+        )
+
+    def test_as_scalar_query_correlate_off(self):
+        sess = create_session()
+        Address, User = self.classes.Address, self.classes.User
+        query = sess.query(func.count(Address.id))\
+            .filter(Address.user_id==User.id)\
+            .correlate(None)\
+            .as_scalar()
+        query = sess.query(User.name, query)
+        self.assert_compile(query, self.query_not_correlated,
+            dialect=default.DefaultDialect()
+        )
+
+
 class RawSelectTest(QueryTest, AssertsCompiledSQL):
     """compare a bunch of select() tests with the equivalent Query using straight table/columns.
 
@@ -90,10 +169,9 @@ def test_select(self):
             )
 
         # a little tedious here, adding labels to work around Query's auto-labelling.
-        # also correlate needed explicitly.  hmmm.....
         # TODO: can we detect only one table in the "froms" and then turn off use_labels ?
         s = sess.query(addresses.c.id.label('id'), addresses.c.email_address.label('email')).\
-            filter(addresses.c.user_id==users.c.id).correlate(users).statement.alias()
+            filter(addresses.c.user_id==users.c.id).statement.alias()
 
         self.assert_compile(sess.query(users, s.c.email).select_from(users.join(s, s.c.id==users.c.id)).with_labels().statement, 
                 "SELECT users.id AS users_id, users.name AS users_name, anon_1.email AS anon_1_email "