Fixed #12717 -- Corrected a problem with subqueries when using multidb... (d312fa2a) · Commits · Dom Sekotill / django

django/db/models/query.py

+2 −2

Original line number	Diff line number	Diff line
		@@ -796,7 +796,7 @@ class QuerySet(object):
		Returns the internal query's SQL and parameters (as a tuple).
		"""
		obj = self.values("pk")
		if connection == connections[obj.db]:
		if obj._db is None or connection == connections[obj._db]:
		return obj.query.get_compiler(connection=connection).as_nested_sql()
		raise ValueError("Can't do subqueries with queries on different DBs.")

		@@ -918,7 +918,7 @@ class ValuesQuerySet(QuerySet):
		% self.__class__.__name__)

		obj = self._clone()
		if connection == connections[obj.db]:
		if obj._db is None or connection == connections[obj._db]:
		return obj.query.get_compiler(connection=connection).as_nested_sql()
		raise ValueError("Can't do subqueries with queries on different DBs.")

tests/regressiontests/multiple_database/tests.py

+33 −0

Original line number	Diff line number	Diff line
		@@ -655,6 +655,19 @@ class QueryTestCase(TestCase):
		# The editor instance should have a db state
		self.assertEqual(book.editor._state.db, 'other')

		def test_subquery(self):
		"""Make sure as_sql works with subqueries and master/slave."""
		sub = Person.objects.using('other').filter(name='fff')
		qs = Book.objects.filter(editor__in=sub)

		# When you call __str__ on the query object, it doesn't know about using
		# so it falls back to the default. If the subquery explicitly uses a
		# different database, an error should be raised.
		self.assertRaises(ValueError, str, qs.query)

		# Evaluating the query shouldn't work, either
		self.assertRaises(ValueError, list, qs)

		class TestRouter(object):
		# A test router. The behaviour is vaguely master/slave, but the
		# databases aren't assumed to propagate changes.
		@@ -1137,6 +1150,26 @@ class RouterTestCase(TestCase):
		review3.content_object = dive
		self.assertEquals(review3._state.db, 'default')

		def test_subquery(self):
		"""Make sure as_sql works with subqueries and master/slave."""
		# Create a book and author on the other database

		mark = Person.objects.using('other').create(name="Mark Pilgrim")
		dive = Book.objects.using('other').create(title="Dive into Python",
		published=datetime.date(2009, 5, 4),
		editor=mark)

		sub = Person.objects.filter(name='Mark Pilgrim')
		qs = Book.objects.filter(editor__in=sub)

		# When you call __str__ on the query object, it doesn't know about using
		# so it falls back to the default. Don't let routing instructions
		# force the subquery to an incompatible database.
		str(qs.query)

		# If you evaluate the query, it should work, running on 'other'
		self.assertEquals(list(qs.values_list('title', flat=True)), [u'Dive into Python'])

		class AuthTestCase(TestCase):
		multi_db = True