Fixed #1142 -- Added multiple database support.

This monster of a patch is the result of Alex Gaynor's 2009 Google Summer of Code project.
Congratulations to Alex for a job well done.

Big thanks also go to:
 * Justin Bronn for keeping GIS in line with the changes,
 * Karen Tracey and Jani Tiainen for their help testing Oracle support
 * Brett Hoerner, Jon Loyens, and Craig Kimmerer for their feedback.
 * Malcolm Treddinick for his guidance during the GSoC submission process.
 * Simon Willison for driving the original design process
 * Cal Henderson for complaining about ponies he wanted.

... and everyone else too numerous to mention that helped to bring this feature into fruition.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@11952 bcc190cf-cafb-0310-a4f2-bffc1f526a37

1 files changed, 705 insertions, 0 deletions

diff --git a/tests/regressiontests/multiple_database/tests.py b/tests/regressiontests/multiple_database/tests.py
new file mode 100644
index 0000000000..300ed5e0a6
--- /dev/null
+++ b/tests/regressiontests/multiple_database/tests.py
@@ -0,0 +1,705 @@
+import datetime
+import pickle
+
+from django.conf import settings
+from django.contrib.auth.models import User
+from django.db import connections
+from django.test import TestCase
+
+from models import Book, Person, Review, UserProfile
+
+try:
+    # we only have these models if the user is using multi-db, it's safe the
+    # run the tests without them though.
+    from models import Article, article_using
+except ImportError:
+    pass
+
+class QueryTestCase(TestCase):
+    multi_db = True
+
+    def test_default_creation(self):
+        "Objects created on the default database don't leak onto other databases"
+        # Create a book on the default database using create()
+        Book.objects.create(title="Pro Django",
+                            published=datetime.date(2008, 12, 16))
+
+        # Create a book on the default database using a save
+        dive = Book()
+        dive.title="Dive into Python"
+        dive.published = datetime.date(2009, 5, 4)
+        dive.save()
+
+        # Check that book exists on the default database, but not on other database
+        try:
+            Book.objects.get(title="Pro Django")
+            Book.objects.using('default').get(title="Pro Django")
+        except Book.DoesNotExist:
+            self.fail('"Dive Into Python" should exist on default database')
+
+        self.assertRaises(Book.DoesNotExist,
+            Book.objects.using('other').get,
+            title="Pro Django"
+        )
+
+        try:
+            Book.objects.get(title="Dive into Python")
+            Book.objects.using('default').get(title="Dive into Python")
+        except Book.DoesNotExist:
+            self.fail('"Dive into Python" should exist on default database')
+
+        self.assertRaises(Book.DoesNotExist,
+            Book.objects.using('other').get,
+            title="Dive into Python"
+        )
+
+
+    def test_other_creation(self):
+        "Objects created on another database don't leak onto the default database"
+        # Create a book on the second database
+        Book.objects.using('other').create(title="Pro Django",
+                                           published=datetime.date(2008, 12, 16))
+
+        # Create a book on the default database using a save
+        dive = Book()
+        dive.title="Dive into Python"
+        dive.published = datetime.date(2009, 5, 4)
+        dive.save(using='other')
+
+        # Check that book exists on the default database, but not on other database
+        try:
+            Book.objects.using('other').get(title="Pro Django")
+        except Book.DoesNotExist:
+            self.fail('"Dive Into Python" should exist on other database')
+
+        self.assertRaises(Book.DoesNotExist,
+            Book.objects.get,
+            title="Pro Django"
+        )
+        self.assertRaises(Book.DoesNotExist,
+            Book.objects.using('default').get,
+            title="Pro Django"
+        )
+
+        try:
+            Book.objects.using('other').get(title="Dive into Python")
+        except Book.DoesNotExist:
+            self.fail('"Dive into Python" should exist on other database')
+
+        self.assertRaises(Book.DoesNotExist,
+            Book.objects.get,
+            title="Dive into Python"
+        )
+        self.assertRaises(Book.DoesNotExist,
+            Book.objects.using('default').get,
+            title="Dive into Python"
+        )
+
+    def test_basic_queries(self):
+        "Queries are constrained to a single database"
+        dive = Book.objects.using('other').create(title="Dive into Python",
+                                                  published=datetime.date(2009, 5, 4))
+
+        dive =  Book.objects.using('other').get(published=datetime.date(2009, 5, 4))
+        self.assertEqual(dive.title, "Dive into Python")
+        self.assertRaises(Book.DoesNotExist, Book.objects.using('default').get, published=datetime.date(2009, 5, 4))
+
+        dive = Book.objects.using('other').get(title__icontains="dive")
+        self.assertEqual(dive.title, "Dive into Python")
+        self.assertRaises(Book.DoesNotExist, Book.objects.using('default').get, title__icontains="dive")
+
+        dive = Book.objects.using('other').get(title__iexact="dive INTO python")
+        self.assertEqual(dive.title, "Dive into Python")
+        self.assertRaises(Book.DoesNotExist, Book.objects.using('default').get, title__iexact="dive INTO python")
+
+        dive =  Book.objects.using('other').get(published__year=2009)
+        self.assertEqual(dive.title, "Dive into Python")
+        self.assertEqual(dive.published, datetime.date(2009, 5, 4))
+        self.assertRaises(Book.DoesNotExist, Book.objects.using('default').get, published__year=2009)
+
+        years = Book.objects.using('other').dates('published', 'year')
+        self.assertEqual([o.year for o in years], [2009])
+        years = Book.objects.using('default').dates('published', 'year')
+        self.assertEqual([o.year for o in years], [])
+
+        months = Book.objects.using('other').dates('published', 'month')
+        self.assertEqual([o.month for o in months], [5])
+        months = Book.objects.using('default').dates('published', 'month')
+        self.assertEqual([o.month for o in months], [])
+
+    def test_m2m_separation(self):
+        "M2M fields are constrained to a single database"
+        # Create a book and author on the default database
+        pro = Book.objects.create(title="Pro Django",
+                                  published=datetime.date(2008, 12, 16))
+
+        marty = Person.objects.create(name="Marty Alchin")
+
+        # Create a book and author on the other database
+        dive = Book.objects.using('other').create(title="Dive into Python",
+                                                  published=datetime.date(2009, 5, 4))
+
+        mark = Person.objects.using('other').create(name="Mark Pilgrim")
+
+        # Save the author relations
+        pro.authors = [marty]
+        dive.authors = [mark]
+
+        # Inspect the m2m tables directly.
+        # There should be 1 entry in each database
+        self.assertEquals(Book.authors.through.objects.using('default').count(), 1)
+        self.assertEquals(Book.authors.through.objects.using('other').count(), 1)
+
+        # Check that queries work across m2m joins
+        self.assertEquals(list(Book.objects.using('default').filter(authors__name='Marty Alchin').values_list('title', flat=True)),
+                          [u'Pro Django'])
+        self.assertEquals(list(Book.objects.using('other').filter(authors__name='Marty Alchin').values_list('title', flat=True)),
+                          [])
+
+        self.assertEquals(list(Book.objects.using('default').filter(authors__name='Mark Pilgrim').values_list('title', flat=True)),
+                          [])
+        self.assertEquals(list(Book.objects.using('other').filter(authors__name='Mark Pilgrim').values_list('title', flat=True)),
+                          [u'Dive into Python'])
+
+        # Reget the objects to clear caches
+        dive = Book.objects.using('other').get(title="Dive into Python")
+        mark = Person.objects.using('other').get(name="Mark Pilgrim")
+
+        # Retrive related object by descriptor. Related objects should be database-baound
+        self.assertEquals(list(dive.authors.all().values_list('name', flat=True)),
+                          [u'Mark Pilgrim'])
+
+        self.assertEquals(list(mark.book_set.all().values_list('title', flat=True)),
+                          [u'Dive into Python'])
+
+    def test_m2m_forward_operations(self):
+        "M2M forward manipulations are all constrained to a single DB"
+        # Create a book and author on the other database
+        dive = Book.objects.using('other').create(title="Dive into Python",
+                                                  published=datetime.date(2009, 5, 4))
+
+        mark = Person.objects.using('other').create(name="Mark Pilgrim")
+
+        # Save the author relations
+        dive.authors = [mark]
+
+        # Add a second author
+        john = Person.objects.using('other').create(name="John Smith")
+        self.assertEquals(list(Book.objects.using('other').filter(authors__name='John Smith').values_list('title', flat=True)),
+                          [])
+
+
+        dive.authors.add(john)
+        self.assertEquals(list(Book.objects.using('other').filter(authors__name='Mark Pilgrim').values_list('title', flat=True)),
+                          [u'Dive into Python'])
+        self.assertEquals(list(Book.objects.using('other').filter(authors__name='John Smith').values_list('title', flat=True)),
+                          [u'Dive into Python'])
+
+        # Remove the second author
+        dive.authors.remove(john)
+        self.assertEquals(list(Book.objects.using('other').filter(authors__name='Mark Pilgrim').values_list('title', flat=True)),
+                          [u'Dive into Python'])
+        self.assertEquals(list(Book.objects.using('other').filter(authors__name='John Smith').values_list('title', flat=True)),
+                          [])
+
+        # Clear all authors
+        dive.authors.clear()
+        self.assertEquals(list(Book.objects.using('other').filter(authors__name='Mark Pilgrim').values_list('title', flat=True)),
+                          [])
+        self.assertEquals(list(Book.objects.using('other').filter(authors__name='John Smith').values_list('title', flat=True)),
+                          [])
+
+        # Create an author through the m2m interface
+        dive.authors.create(name='Jane Brown')
+        self.assertEquals(list(Book.objects.using('other').filter(authors__name='Mark Pilgrim').values_list('title', flat=True)),
+                          [])
+        self.assertEquals(list(Book.objects.using('other').filter(authors__name='Jane Brown').values_list('title', flat=True)),
+                          [u'Dive into Python'])
+
+    def test_m2m_reverse_operations(self):
+        "M2M reverse manipulations are all constrained to a single DB"
+        # Create a book and author on the other database
+        dive = Book.objects.using('other').create(title="Dive into Python",
+                                                  published=datetime.date(2009, 5, 4))
+
+        mark = Person.objects.using('other').create(name="Mark Pilgrim")
+
+        # Save the author relations
+        dive.authors = [mark]
+
+        # Create a second book on the other database
+        grease = Book.objects.using('other').create(title="Greasemonkey Hacks",
+                                                    published=datetime.date(2005, 11, 1))
+
+        # Add a books to the m2m
+        mark.book_set.add(grease)
+        self.assertEquals(list(Person.objects.using('other').filter(book__title='Dive into Python').values_list('name', flat=True)),
+                          [u'Mark Pilgrim'])
+        self.assertEquals(list(Person.objects.using('other').filter(book__title='Greasemonkey Hacks').values_list('name', flat=True)),
+                          [u'Mark Pilgrim'])
+
+        # Remove a book from the m2m
+        mark.book_set.remove(grease)
+        self.assertEquals(list(Person.objects.using('other').filter(book__title='Dive into Python').values_list('name', flat=True)),
+                          [u'Mark Pilgrim'])
+        self.assertEquals(list(Person.objects.using('other').filter(book__title='Greasemonkey Hacks').values_list('name', flat=True)),
+                          [])
+
+        # Clear the books associated with mark
+        mark.book_set.clear()
+        self.assertEquals(list(Person.objects.using('other').filter(book__title='Dive into Python').values_list('name', flat=True)),
+                          [])
+        self.assertEquals(list(Person.objects.using('other').filter(book__title='Greasemonkey Hacks').values_list('name', flat=True)),
+                          [])
+
+        # Create a book through the m2m interface
+        mark.book_set.create(title="Dive into HTML5", published=datetime.date(2020, 1, 1))
+        self.assertEquals(list(Person.objects.using('other').filter(book__title='Dive into Python').values_list('name', flat=True)),
+                          [])
+        self.assertEquals(list(Person.objects.using('other').filter(book__title='Dive into HTML5').values_list('name', flat=True)),
+                          [u'Mark Pilgrim'])
+
+#    def test_m2m_cross_database_protection(self):
+#        "Operations that involve sharing M2M objects across databases raise an error"
+#        # Create a book and author on the default database
+#        pro = Book.objects.create(title="Pro Django",
+#                                  published=datetime.date(2008, 12, 16))
+
+#        marty = Person.objects.create(name="Marty Alchin")
+
+#        # Create a book and author on the other database
+#        dive = Book.objects.using('other').create(title="Dive into Python",
+#                                                  published=datetime.date(2009, 5, 4))
+
+#        mark = Person.objects.using('other').create(name="Mark Pilgrim")
+#        # Set a foreign key set with an object from a different database
+#        try:
+#            marty.book_set = [pro, dive]
+#            self.fail("Shouldn't be able to assign across databases")
+#        except ValueError:
+#            pass
+
+#        # Add to an m2m with an object from a different database
+#        try:
+#            marty.book_set.add(dive)
+#            self.fail("Shouldn't be able to assign across databases")
+#        except ValueError:
+#            pass
+
+#        # Set a m2m with an object from a different database
+#        try:
+#            marty.book_set = [pro, dive]
+#            self.fail("Shouldn't be able to assign across databases")
+#        except ValueError:
+#            pass
+
+#        # Add to a reverse m2m with an object from a different database
+#        try:
+#            dive.authors.add(marty)
+#            self.fail("Shouldn't be able to assign across databases")
+#        except ValueError:
+#            pass
+
+#        # Set a reverse m2m with an object from a different database
+#        try:
+#            dive.authors = [mark, marty]
+#            self.fail("Shouldn't be able to assign across databases")
+#        except ValueError:
+#            pass
+
+    def test_foreign_key_separation(self):
+        "FK fields are constrained to a single database"
+        # Create a book and author on the default database
+        pro = Book.objects.create(title="Pro Django",
+                                  published=datetime.date(2008, 12, 16))
+
+        marty = Person.objects.create(name="Marty Alchin")
+        george = Person.objects.create(name="George Vilches")
+
+        # Create a book and author on the other database
+        dive = Book.objects.using('other').create(title="Dive into Python",
+                                                  published=datetime.date(2009, 5, 4))
+
+        mark = Person.objects.using('other').create(name="Mark Pilgrim")
+        chris = Person.objects.using('other').create(name="Chris Mills")
+
+        # Save the author's favourite books
+        pro.editor = george
+        pro.save()
+
+        dive.editor = chris
+        dive.save()
+
+        pro = Book.objects.using('default').get(title="Pro Django")
+        self.assertEquals(pro.editor.name, "George Vilches")
+
+        dive = Book.objects.using('other').get(title="Dive into Python")
+        self.assertEquals(dive.editor.name, "Chris Mills")
+
+        # Check that queries work across foreign key joins
+        self.assertEquals(list(Person.objects.using('default').filter(edited__title='Pro Django').values_list('name', flat=True)),
+                          [u'George Vilches'])
+        self.assertEquals(list(Person.objects.using('other').filter(edited__title='Pro Django').values_list('name', flat=True)),
+                          [])
+
+        self.assertEquals(list(Person.objects.using('default').filter(edited__title='Dive into Python').values_list('name', flat=True)),
+                          [])
+        self.assertEquals(list(Person.objects.using('other').filter(edited__title='Dive into Python').values_list('name', flat=True)),
+                          [u'Chris Mills'])
+
+        # Reget the objects to clear caches
+        chris = Person.objects.using('other').get(name="Chris Mills")
+        dive = Book.objects.using('other').get(title="Dive into Python")
+
+        # Retrive related object by descriptor. Related objects should be database-baound
+        self.assertEquals(list(chris.edited.values_list('title', flat=True)),
+                          [u'Dive into Python'])
+
+    def test_foreign_key_reverse_operations(self):
+        "FK reverse manipulations are all constrained to a single DB"
+        dive = Book.objects.using('other').create(title="Dive into Python",
+                                                       published=datetime.date(2009, 5, 4))
+
+        mark = Person.objects.using('other').create(name="Mark Pilgrim")
+        chris = Person.objects.using('other').create(name="Chris Mills")
+
+        # Save the author relations
+        dive.editor = chris
+        dive.save()
+
+        # Add a second book edited by chris
+        html5 = Book.objects.using('other').create(title="Dive into HTML5", published=datetime.date(2010, 3, 15))
+        self.assertEquals(list(Person.objects.using('other').filter(edited__title='Dive into HTML5').values_list('name', flat=True)),
+                          [])
+
+        chris.edited.add(html5)
+        self.assertEquals(list(Person.objects.using('other').filter(edited__title='Dive into HTML5').values_list('name', flat=True)),
+                          [u'Chris Mills'])
+        self.assertEquals(list(Person.objects.using('other').filter(edited__title='Dive into Python').values_list('name', flat=True)),
+                          [u'Chris Mills'])
+
+        # Remove the second editor
+        chris.edited.remove(html5)
+        self.assertEquals(list(Person.objects.using('other').filter(edited__title='Dive into HTML5').values_list('name', flat=True)),
+                          [])
+        self.assertEquals(list(Person.objects.using('other').filter(edited__title='Dive into Python').values_list('name', flat=True)),
+                          [u'Chris Mills'])
+
+        # Clear all edited books
+        chris.edited.clear()
+        self.assertEquals(list(Person.objects.using('other').filter(edited__title='Dive into HTML5').values_list('name', flat=True)),
+                          [])
+        self.assertEquals(list(Person.objects.using('other').filter(edited__title='Dive into Python').values_list('name', flat=True)),
+                          [])
+
+        # Create an author through the m2m interface
+        chris.edited.create(title='Dive into Water', published=datetime.date(2010, 3, 15))
+        self.assertEquals(list(Person.objects.using('other').filter(edited__title='Dive into HTML5').values_list('name', flat=True)),
+                          [])
+        self.assertEquals(list(Person.objects.using('other').filter(edited__title='Dive into Water').values_list('name', flat=True)),
+                          [u'Chris Mills'])
+        self.assertEquals(list(Person.objects.using('other').filter(edited__title='Dive into Python').values_list('name', flat=True)),
+                          [])
+
+#    def test_foreign_key_cross_database_protection(self):
+#        "Operations that involve sharing FK objects across databases raise an error"
+#        # Create a book and author on the default database
+#        pro = Book.objects.create(title="Pro Django",
+#                                  published=datetime.date(2008, 12, 16))
+
+#        marty = Person.objects.create(name="Marty Alchin")
+
+#        # Create a book and author on the other database
+#        dive = Book.objects.using('other').create(title="Dive into Python",
+#                                                  published=datetime.date(2009, 5, 4))
+
+#        mark = Person.objects.using('other').create(name="Mark Pilgrim")
+
+#        # Set a foreign key with an object from a different database
+#        try:
+#            dive.editor = marty
+#            self.fail("Shouldn't be able to assign across databases")
+#        except ValueError:
+#            pass
+
+#        # Set a foreign key set with an object from a different database
+#        try:
+#            marty.edited = [pro, dive]
+#            self.fail("Shouldn't be able to assign across databases")
+#        except ValueError:
+#            pass
+
+#        # Add to a foreign key set with an object from a different database
+#        try:
+#            marty.edited.add(dive)
+#            self.fail("Shouldn't be able to assign across databases")
+#        except ValueError:
+#            pass
+
+#        # BUT! if you assign a FK object when the base object hasn't
+#        # been saved yet, you implicitly assign the database for the
+#        # base object.
+#        chris = Person(name="Chris Mills")
+#        html5 = Book(title="Dive into HTML5", published=datetime.date(2010, 3, 15))
+#        # initially, no db assigned
+#        self.assertEquals(chris._state.db, None)
+#        self.assertEquals(html5._state.db, None)
+
+#        # old object comes from 'other', so the new object is set to use 'other'...
+#        dive.editor = chris
+#        html5.editor = mark
+#        # self.assertEquals(chris._state.db, 'other')
+#        self.assertEquals(html5._state.db, 'other')
+#        # ... but it isn't saved yet
+#        self.assertEquals(list(Person.objects.using('other').values_list('name',flat=True)),
+#                          [u'Mark Pilgrim'])
+#        self.assertEquals(list(Book.objects.using('other').values_list('title',flat=True)),
+#                           [u'Dive into Python'])
+
+#        # When saved (no using required), new objects goes to 'other'
+#        chris.save()
+#        html5.save()
+#        self.assertEquals(list(Person.objects.using('default').values_list('name',flat=True)),
+#                          [u'Marty Alchin'])
+#        self.assertEquals(list(Person.objects.using('other').values_list('name',flat=True)),
+#                          [u'Chris Mills', u'Mark Pilgrim'])
+#        self.assertEquals(list(Book.objects.using('default').values_list('title',flat=True)),
+#                          [u'Pro Django'])
+#        self.assertEquals(list(Book.objects.using('other').values_list('title',flat=True)),
+#                          [u'Dive into HTML5', u'Dive into Python'])
+
+#        # This also works if you assign the FK in the constructor
+#        water = Book(title="Dive into Water", published=datetime.date(2001, 1, 1), editor=mark)
+#        self.assertEquals(water._state.db, 'other')
+#        # ... but it isn't saved yet
+#        self.assertEquals(list(Book.objects.using('default').values_list('title',flat=True)),
+#                          [u'Pro Django'])
+#        self.assertEquals(list(Book.objects.using('other').values_list('title',flat=True)),
+#                          [u'Dive into HTML5', u'Dive into Python'])
+
+#        # When saved, the new book goes to 'other'
+#        water.save()
+#        self.assertEquals(list(Book.objects.using('default').values_list('title',flat=True)),
+#                          [u'Pro Django'])
+#        self.assertEquals(list(Book.objects.using('other').values_list('title',flat=True)),
+#                          [u'Dive into HTML5', u'Dive into Python', u'Dive into Water'])
+
+    def test_generic_key_separation(self):
+        "Generic fields are constrained to a single database"
+        # Create a book and author on the default database
+        pro = Book.objects.create(title="Pro Django",
+                                  published=datetime.date(2008, 12, 16))
+
+        review1 = Review.objects.create(source="Python Monthly", content_object=pro)
+
+        # Create a book and author on the other database
+        dive = Book.objects.using('other').create(title="Dive into Python",
+                                                  published=datetime.date(2009, 5, 4))
+
+        review2 = Review.objects.using('other').create(source="Python Weekly", content_object=dive)
+
+        review1 = Review.objects.using('default').get(source="Python Monthly")
+        self.assertEquals(review1.content_object.title, "Pro Django")
+
+        review2 = Review.objects.using('other').get(source="Python Weekly")
+        self.assertEquals(review2.content_object.title, "Dive into Python")
+
+        # Reget the objects to clear caches
+        dive = Book.objects.using('other').get(title="Dive into Python")
+
+        # Retrive related object by descriptor. Related objects should be database-bound
+        self.assertEquals(list(dive.reviews.all().values_list('source', flat=True)),
+                          [u'Python Weekly'])
+
+    def test_generic_key_reverse_operations(self):
+        "Generic reverse manipulations are all constrained to a single DB"
+        dive = Book.objects.using('other').create(title="Dive into Python",
+                                                  published=datetime.date(2009, 5, 4))
+
+        temp = Book.objects.using('other').create(title="Temp",
+                                                  published=datetime.date(2009, 5, 4))
+
+        review1 = Review.objects.using('other').create(source="Python Weekly", content_object=dive)
+        review2 = Review.objects.using('other').create(source="Python Monthly", content_object=temp)
+
+        self.assertEquals(list(Review.objects.using('default').filter(object_id=dive.pk).values_list('source', flat=True)),
+                          [])
+        self.assertEquals(list(Review.objects.using('other').filter(object_id=dive.pk).values_list('source', flat=True)),
+                          [u'Python Weekly'])
+
+        # Add a second review
+        dive.reviews.add(review2)
+        self.assertEquals(list(Review.objects.using('default').filter(object_id=dive.pk).values_list('source', flat=True)),
+                          [])
+        self.assertEquals(list(Review.objects.using('other').filter(object_id=dive.pk).values_list('source', flat=True)),
+                          [u'Python Monthly', u'Python Weekly'])
+
+        # Remove the second author
+        dive.reviews.remove(review1)
+        self.assertEquals(list(Review.objects.using('default').filter(object_id=dive.pk).values_list('source', flat=True)),
+                          [])
+        self.assertEquals(list(Review.objects.using('other').filter(object_id=dive.pk).values_list('source', flat=True)),
+                          [u'Python Monthly'])
+
+        # Clear all reviews
+        dive.reviews.clear()
+        self.assertEquals(list(Review.objects.using('default').filter(object_id=dive.pk).values_list('source', flat=True)),
+                          [])
+        self.assertEquals(list(Review.objects.using('other').filter(object_id=dive.pk).values_list('source', flat=True)),
+                          [])
+
+        # Create an author through the generic interface
+        dive.reviews.create(source='Python Daily')
+        self.assertEquals(list(Review.objects.using('default').filter(object_id=dive.pk).values_list('source', flat=True)),
+                          [])
+        self.assertEquals(list(Review.objects.using('other').filter(object_id=dive.pk).values_list('source', flat=True)),
+                          [u'Python Daily'])
+
+#    def test_generic_key_cross_database_protection(self):
+##        "Operations that involve sharing FK objects across databases raise an error"
+##        # Create a book and author on the default database
+##        pro = Book.objects.create(title="Pro Django",
+##                                  published=datetime.date(2008, 12, 16))
+
+##        review1 = Review.objects.create(source="Python Monthly", content_object=pro)
+
+##        # Create a book and author on the other database
+##        dive = Book.objects.using('other').create(title="Dive into Python",
+##                                                  published=datetime.date(2009, 5, 4))
+
+##        review2 = Review.objects.using('other').create(source="Python Weekly", content_object=dive)
+
+##        # Set a foreign key with an object from a different database
+##        try:
+##            review1.content_object = dive
+##            self.fail("Shouldn't be able to assign across databases")
+##        except ValueError:
+##            pass
+
+#        # Add to a foreign key set with an object from a different database
+#        try:
+#            dive.reviews.add(review1)
+#            self.fail("Shouldn't be able to assign across databases")
+#        except ValueError:
+#            pass
+
+#        # BUT! if you assign a FK object when the base object hasn't
+#        # been saved yet, you implicitly assign the database for the
+#        # base object.
+#        review3 = Review(source="Python Daily")
+#        # initially, no db assigned
+#        self.assertEquals(review3._state.db, None)
+
+#        # Dive comes from 'other', so review3 is set to use 'other'...
+#        review3.content_object = dive
+#        self.assertEquals(review3._state.db, 'other')
+#        # ... but it isn't saved yet
+#        self.assertEquals(list(Review.objects.using('default').filter(object_id=pro.pk).values_list('source', flat=True)),
+#                          [u'Python Monthly'])
+#        self.assertEquals(list(Review.objects.using('other').filter(object_id=dive.pk).values_list('source',flat=True)),
+#                          [u'Python Weekly'])
+
+#        # When saved, John goes to 'other'
+#        review3.save()
+#        self.assertEquals(list(Review.objects.using('default').filter(object_id=pro.pk).values_list('source', flat=True)),
+#                          [u'Python Monthly'])
+#        self.assertEquals(list(Review.objects.using('other').filter(object_id=dive.pk).values_list('source',flat=True)),
+#                          [u'Python Daily', u'Python Weekly'])
+
+    def test_ordering(self):
+        "get_next_by_XXX commands stick to a single database"
+        pro = Book.objects.create(title="Pro Django",
+                                  published=datetime.date(2008, 12, 16))
+
+        dive = Book.objects.using('other').create(title="Dive into Python",
+                                                  published=datetime.date(2009, 5, 4))
+
+        learn = Book.objects.using('other').create(title="Learning Python",
+                                                   published=datetime.date(2008, 7, 16))
+
+        self.assertEquals(learn.get_next_by_published().title, "Dive into Python")
+        self.assertEquals(dive.get_previous_by_published().title, "Learning Python")
+
+    def test_raw(self):
+        "test the raw() method across databases"
+        dive = Book.objects.using('other').create(title="Dive into Python",
+            published=datetime.date(2009, 5, 4))
+        val = Book.objects.db_manager("other").raw('SELECT id FROM "multiple_database_book"')
+        self.assertEqual(map(lambda o: o.pk, val), [dive.pk])
+
+        val = Book.objects.raw('SELECT id FROM "multiple_database_book"').using('other')
+        self.assertEqual(map(lambda o: o.pk, val), [dive.pk])
+
+
+class UserProfileTestCase(TestCase):
+    def setUp(self):
+        self.old_auth_profile_module = getattr(settings, 'AUTH_PROFILE_MODULE', None)
+        settings.AUTH_PROFILE_MODULE = 'multiple_database.UserProfile'
+
+    def tearDown(self):
+        settings.AUTH_PROFILE_MODULE = self.old_auth_profile_module
+
+    def test_user_profiles(self):
+
+        alice = User.objects.create_user('alice', 'alice@example.com')
+        bob = User.objects.db_manager('other').create_user('bob', 'bob@example.com')
+
+        alice_profile = UserProfile(user=alice, flavor='chocolate')
+        alice_profile.save()
+
+        bob_profile = UserProfile(user=bob, flavor='crunchy frog')
+        bob_profile.save()
+
+        self.assertEquals(alice.get_profile().flavor, 'chocolate')
+        self.assertEquals(bob.get_profile().flavor, 'crunchy frog')
+
+class FixtureTestCase(TestCase):
+    multi_db = True
+    fixtures = ['multidb-common', 'multidb']
+
+    def test_fixture_loading(self):
+        "Multi-db fixtures are loaded correctly"
+        # Check that "Pro Django" exists on the default database, but not on other database
+        try:
+            Book.objects.get(title="Pro Django")
+            Book.objects.using('default').get(title="Pro Django")
+        except Book.DoesNotExist:
+            self.fail('"Pro Django" should exist on default database')
+
+        self.assertRaises(Book.DoesNotExist,
+            Book.objects.using('other').get,
+            title="Pro Django"
+        )
+
+        # Check that "Dive into Python" exists on the default database, but not on other database
+        try:
+            Book.objects.using('other').get(title="Dive into Python")
+        except Book.DoesNotExist:
+            self.fail('"Dive into Python" should exist on other database')
+
+        self.assertRaises(Book.DoesNotExist,
+            Book.objects.get,
+            title="Dive into Python"
+        )
+        self.assertRaises(Book.DoesNotExist,
+            Book.objects.using('default').get,
+            title="Dive into Python"
+        )
+
+        # Check that "Definitive Guide" exists on the both databases
+        try:
+            Book.objects.get(title="The Definitive Guide to Django")
+            Book.objects.using('default').get(title="The Definitive Guide to Django")
+            Book.objects.using('other').get(title="The Definitive Guide to Django")
+        except Book.DoesNotExist:
+            self.fail('"The Definitive Guide to Django" should exist on both databases')
+
+
+class PickleQuerySetTestCase(TestCase):
+    multi_db = True
+
+    def test_pickling(self):
+        for db in connections:
+            Book.objects.using(db).create(title='Dive into Python', published=datetime.date(2009, 5, 4))
+            qs = Book.objects.all()
+            self.assertEqual(qs.db, pickle.loads(pickle.dumps(qs)).db)