Fixed #17260 -- Added time zone aware aggregation and lookups.

Thanks Carl Meyer for the review.

Squashed commit of the following:

commit 4f290bdb60b7d8534abf4ca901bd0844612dcbda
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Wed Feb 13 21:21:30 2013 +0100

    Used '0:00' instead of 'UTC' which doesn't always exist in Oracle.

    Thanks Ian Kelly for the suggestion.

commit 01b6366f3ce67d57a58ca8f25e5be77911748638
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Wed Feb 13 13:38:43 2013 +0100

    Made tzname a parameter of datetime_extract/trunc_sql.

    This is required to work around a bug in Oracle.

commit 924a144ef8a80ba4daeeafbe9efaa826566e9d02
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Wed Feb 13 14:47:44 2013 +0100

    Added support for parameters in SELECT clauses.

commit b4351d2890cd1090d3ff2d203fe148937324c935
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Mon Feb 11 22:30:22 2013 +0100

    Documented backwards incompatibilities in the two previous commits.

commit 91ef84713c81bd455f559dacf790e586d08cacb9
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Mon Feb 11 09:42:31 2013 +0100

    Used QuerySet.datetimes for the admin's date_hierarchy.

commit 0d0de288a5210fa106cd4350961eb2006535cc5c
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Mon Feb 11 09:29:38 2013 +0100

    Used QuerySet.datetimes in date-based generic views.

commit 9c0859ff7c0b00734afe7fc15609d43d83215072
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Sun Feb 10 21:43:25 2013 +0100

    Implemented QuerySet.datetimes on Oracle.

commit 68ab511a4ffbd2b811bf5da174d47e4dd90f28fc
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Sun Feb 10 21:43:14 2013 +0100

    Implemented QuerySet.datetimes on MySQL.

commit 22d52681d347a8cdf568dc31ed032cbc61d049ef
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Sun Feb 10 21:42:29 2013 +0100

    Implemented QuerySet.datetimes on SQLite.

commit f6800fd04c93722b45f9236976389e0b2fe436f5
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Sun Feb 10 21:43:03 2013 +0100

    Implemented QuerySet.datetimes on PostgreSQL.

commit 0c829c23f4cf4d6804cadcc93032dd4c26b8c65e
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Sun Feb 10 21:41:08 2013 +0100

    Added datetime-handling infrastructure in the ORM layers.

commit 104d82a7778cf3f0f5d03dfa53709c26df45daad
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Mon Feb 11 10:05:55 2013 +0100

    Updated null_queries tests to avoid clashing with the __second lookup.

commit c01bbb32358201b3ac8cb4291ef87b7612a2b8e6
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Sun Feb 10 23:07:41 2013 +0100

    Updated tests of .dates().

    Replaced .dates() by .datetimes() for DateTimeFields.
    Replaced dates with datetimes in the expected output for DateFields.

commit 50fb7a52462fecf0127b38e7f3df322aeb287c43
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Sun Feb 10 21:40:09 2013 +0100

    Updated and added tests for QuerySet.datetimes.

commit a8451a5004c437190e264667b1e6fb8acc3c1eeb
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Sun Feb 10 22:34:46 2013 +0100

    Documented the new time lookups and updated the date lookups.

commit 29413eab2bd1d5e004598900c0dadc0521bbf4d3
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date:   Sun Feb 10 16:15:49 2013 +0100

    Documented QuerySet.datetimes and updated QuerySet.dates.

13 files changed, 168 insertions, 50 deletions

diff --git a/tests/regressiontests/aggregation_regress/tests.py b/tests/regressiontests/aggregation_regress/tests.py
index 596ebbfaec..076567538b 100644
--- a/tests/regressiontests/aggregation_regress/tests.py
+++ b/tests/regressiontests/aggregation_regress/tests.py
@@ -546,8 +546,8 @@ class AggregationTests(TestCase):
         qs = Book.objects.annotate(num_authors=Count('authors')).filter(num_authors=2).dates('pubdate', 'day')
         self.assertQuerysetEqual(
             qs, [
-                datetime.datetime(1995, 1, 15, 0, 0),
-                datetime.datetime(2007, 12, 6, 0, 0)
+                datetime.date(1995, 1, 15),
+                datetime.date(2007, 12, 6),
             ],
             lambda b: b
         )
diff --git a/tests/regressiontests/backends/tests.py b/tests/regressiontests/backends/tests.py
index 313fdc8351..fbe5026e12 100644
--- a/tests/regressiontests/backends/tests.py
+++ b/tests/regressiontests/backends/tests.py
@@ -144,11 +144,11 @@ class DateQuotingTest(TestCase):
         updated = datetime.datetime(2010, 2, 20)
         models.SchoolClass.objects.create(year=2009, last_updated=updated)
         years = models.SchoolClass.objects.dates('last_updated', 'year')
-        self.assertEqual(list(years), [datetime.datetime(2010, 1, 1, 0, 0)])
+        self.assertEqual(list(years), [datetime.date(2010, 1, 1)])
 
-    def test_django_extract(self):
+    def test_django_date_extract(self):
         """
-        Test the custom ``django_extract method``, in particular against fields
+        Test the custom ``django_date_extract method``, in particular against fields
         which clash with strings passed to it (e.g. 'day') - see #12818__.
 
         __: http://code.djangoproject.com/ticket/12818
diff --git a/tests/regressiontests/dates/models.py b/tests/regressiontests/dates/models.py
index e4bffb7199..23350755e7 100644
--- a/tests/regressiontests/dates/models.py
+++ b/tests/regressiontests/dates/models.py
@@ -1,3 +1,5 @@
+from __future__ import unicode_literals
+
 from django.db import models
 from django.utils.encoding import python_2_unicode_compatible
 
diff --git a/tests/regressiontests/dates/tests.py b/tests/regressiontests/dates/tests.py
index de28cac436..6c02d597de 100644
--- a/tests/regressiontests/dates/tests.py
+++ b/tests/regressiontests/dates/tests.py
@@ -1,6 +1,6 @@
 from __future__ import absolute_import
 
-from datetime import datetime
+import datetime
 
 from django.test import TestCase
 
@@ -11,32 +11,32 @@ class DatesTests(TestCase):
     def test_related_model_traverse(self):
         a1 = Article.objects.create(
             title="First one",
-            pub_date=datetime(2005, 7, 28),
+            pub_date=datetime.date(2005, 7, 28),
         )
         a2 = Article.objects.create(
             title="Another one",
-            pub_date=datetime(2010, 7, 28),
+            pub_date=datetime.date(2010, 7, 28),
         )
         a3 = Article.objects.create(
             title="Third one, in the first day",
-            pub_date=datetime(2005, 7, 28),
+            pub_date=datetime.date(2005, 7, 28),
         )
 
         a1.comments.create(
             text="Im the HULK!",
-            pub_date=datetime(2005, 7, 28),
+            pub_date=datetime.date(2005, 7, 28),
         )
         a1.comments.create(
             text="HULK SMASH!",
-            pub_date=datetime(2005, 7, 29),
+            pub_date=datetime.date(2005, 7, 29),
         )
         a2.comments.create(
             text="LMAO",
-            pub_date=datetime(2010, 7, 28),
+            pub_date=datetime.date(2010, 7, 28),
         )
         a3.comments.create(
             text="+1",
-            pub_date=datetime(2005, 8, 29),
+            pub_date=datetime.date(2005, 8, 29),
         )
 
         c = Category.objects.create(name="serious-news")
@@ -44,31 +44,31 @@ class DatesTests(TestCase):
 
         self.assertQuerysetEqual(
             Comment.objects.dates("article__pub_date", "year"), [
-                datetime(2005, 1, 1),
-                datetime(2010, 1, 1),
+                datetime.date(2005, 1, 1),
+                datetime.date(2010, 1, 1),
             ],
             lambda d: d,
         )
         self.assertQuerysetEqual(
             Comment.objects.dates("article__pub_date", "month"), [
-                datetime(2005, 7, 1),
-                datetime(2010, 7, 1),
+                datetime.date(2005, 7, 1),
+                datetime.date(2010, 7, 1),
             ],
             lambda d: d
         )
         self.assertQuerysetEqual(
             Comment.objects.dates("article__pub_date", "day"), [
-                datetime(2005, 7, 28),
-                datetime(2010, 7, 28),
+                datetime.date(2005, 7, 28),
+                datetime.date(2010, 7, 28),
             ],
             lambda d: d
         )
         self.assertQuerysetEqual(
             Article.objects.dates("comments__pub_date", "day"), [
-                datetime(2005, 7, 28),
-                datetime(2005, 7, 29),
-                datetime(2005, 8, 29),
-                datetime(2010, 7, 28),
+                datetime.date(2005, 7, 28),
+                datetime.date(2005, 7, 29),
+                datetime.date(2005, 8, 29),
+                datetime.date(2010, 7, 28),
             ],
             lambda d: d
         )
@@ -77,7 +77,7 @@ class DatesTests(TestCase):
         )
         self.assertQuerysetEqual(
             Category.objects.dates("articles__pub_date", "day"), [
-                datetime(2005, 7, 28),
+                datetime.date(2005, 7, 28),
             ],
             lambda d: d,
         )
diff --git a/tests/regressiontests/datetimes/__init__.py b/tests/regressiontests/datetimes/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/tests/regressiontests/datetimes/__init__.py
diff --git a/tests/regressiontests/datetimes/models.py b/tests/regressiontests/datetimes/models.py
new file mode 100644
index 0000000000..f21376aa1c
--- /dev/null
+++ b/tests/regressiontests/datetimes/models.py
@@ -0,0 +1,28 @@
+from __future__ import unicode_literals
+
+from django.db import models
+from django.utils.encoding import python_2_unicode_compatible
+
+
+@python_2_unicode_compatible
+class Article(models.Model):
+    title = models.CharField(max_length=100)
+    pub_date = models.DateTimeField()
+
+    categories = models.ManyToManyField("Category", related_name="articles")
+
+    def __str__(self):
+        return self.title
+
+@python_2_unicode_compatible
+class Comment(models.Model):
+    article = models.ForeignKey(Article, related_name="comments")
+    text = models.TextField()
+    pub_date = models.DateTimeField()
+    approval_date = models.DateTimeField(null=True)
+
+    def __str__(self):
+        return 'Comment to %s (%s)' % (self.article.title, self.pub_date)
+
+class Category(models.Model):
+    name = models.CharField(max_length=255)
diff --git a/tests/regressiontests/datetimes/tests.py b/tests/regressiontests/datetimes/tests.py
new file mode 100644
index 0000000000..58cb060f6b
--- /dev/null
+++ b/tests/regressiontests/datetimes/tests.py
@@ -0,0 +1,83 @@
+from __future__ import absolute_import
+
+import datetime
+
+from django.test import TestCase
+
+from .models import Article, Comment, Category
+
+
+class DateTimesTests(TestCase):
+    def test_related_model_traverse(self):
+        a1 = Article.objects.create(
+            title="First one",
+            pub_date=datetime.datetime(2005, 7, 28, 9, 0, 0),
+        )
+        a2 = Article.objects.create(
+            title="Another one",
+            pub_date=datetime.datetime(2010, 7, 28, 10, 0, 0),
+        )
+        a3 = Article.objects.create(
+            title="Third one, in the first day",
+            pub_date=datetime.datetime(2005, 7, 28, 17, 0, 0),
+        )
+
+        a1.comments.create(
+            text="Im the HULK!",
+            pub_date=datetime.datetime(2005, 7, 28, 9, 30, 0),
+        )
+        a1.comments.create(
+            text="HULK SMASH!",
+            pub_date=datetime.datetime(2005, 7, 29, 1, 30, 0),
+        )
+        a2.comments.create(
+            text="LMAO",
+            pub_date=datetime.datetime(2010, 7, 28, 10, 10, 10),
+        )
+        a3.comments.create(
+            text="+1",
+            pub_date=datetime.datetime(2005, 8, 29, 10, 10, 10),
+        )
+
+        c = Category.objects.create(name="serious-news")
+        c.articles.add(a1, a3)
+
+        self.assertQuerysetEqual(
+            Comment.objects.datetimes("article__pub_date", "year"), [
+                datetime.datetime(2005, 1, 1),
+                datetime.datetime(2010, 1, 1),
+            ],
+            lambda d: d,
+        )
+        self.assertQuerysetEqual(
+            Comment.objects.datetimes("article__pub_date", "month"), [
+                datetime.datetime(2005, 7, 1),
+                datetime.datetime(2010, 7, 1),
+            ],
+            lambda d: d
+        )
+        self.assertQuerysetEqual(
+            Comment.objects.datetimes("article__pub_date", "day"), [
+                datetime.datetime(2005, 7, 28),
+                datetime.datetime(2010, 7, 28),
+            ],
+            lambda d: d
+        )
+        self.assertQuerysetEqual(
+            Article.objects.datetimes("comments__pub_date", "day"), [
+                datetime.datetime(2005, 7, 28),
+                datetime.datetime(2005, 7, 29),
+                datetime.datetime(2005, 8, 29),
+                datetime.datetime(2010, 7, 28),
+            ],
+            lambda d: d
+        )
+        self.assertQuerysetEqual(
+            Article.objects.datetimes("comments__approval_date", "day"), []
+        )
+        self.assertQuerysetEqual(
+            Category.objects.datetimes("articles__pub_date", "day"), [
+                datetime.datetime(2005, 7, 28),
+            ],
+            lambda d: d,
+        )
diff --git a/tests/regressiontests/extra_regress/tests.py b/tests/regressiontests/extra_regress/tests.py
index 1bc6789edd..194b250c99 100644
--- a/tests/regressiontests/extra_regress/tests.py
+++ b/tests/regressiontests/extra_regress/tests.py
@@ -166,8 +166,9 @@ class ExtraRegressTests(TestCase):
         )
 
         self.assertQuerysetEqual(
-            RevisionableModel.objects.extra(select={"the_answer": 'id'}).dates('when', 'month'),
-            ['datetime.datetime(2008, 9, 1, 0, 0)']
+            RevisionableModel.objects.extra(select={"the_answer": 'id'}).datetimes('when', 'month'),
+            [datetime.datetime(2008, 9, 1, 0, 0)],
+            transform=lambda d: d,
         )
 
     def test_values_with_extra(self):
diff --git a/tests/regressiontests/generic_views/dates.py b/tests/regressiontests/generic_views/dates.py
index 0c565daf9f..844b10bbcc 100644
--- a/tests/regressiontests/generic_views/dates.py
+++ b/tests/regressiontests/generic_views/dates.py
@@ -4,7 +4,7 @@ import time
 import datetime
 
 from django.core.exceptions import ImproperlyConfigured
-from django.test import TestCase
+from django.test import TestCase, skipUnlessDBFeature
 from django.test.utils import override_settings
 from django.utils import timezone
 from django.utils.unittest import skipUnless
@@ -119,6 +119,7 @@ class ArchiveIndexViewTests(TestCase):
         self.assertEqual(res.status_code, 200)
 
     @requires_tz_support
+    @skipUnlessDBFeature('has_zoneinfo_database')
     @override_settings(USE_TZ=True, TIME_ZONE='Africa/Nairobi')
     def test_aware_datetime_archive_view(self):
         BookSigning.objects.create(event_date=datetime.datetime(2008, 4, 2, 12, 0, tzinfo=timezone.utc))
@@ -140,7 +141,7 @@ class YearArchiveViewTests(TestCase):
     def test_year_view(self):
         res = self.client.get('/dates/books/2008/')
         self.assertEqual(res.status_code, 200)
-        self.assertEqual(list(res.context['date_list']), [datetime.datetime(2008, 10, 1)])
+        self.assertEqual(list(res.context['date_list']), [datetime.date(2008, 10, 1)])
         self.assertEqual(res.context['year'], datetime.date(2008, 1, 1))
         self.assertTemplateUsed(res, 'generic_views/book_archive_year.html')
 
@@ -151,7 +152,7 @@ class YearArchiveViewTests(TestCase):
     def test_year_view_make_object_list(self):
         res = self.client.get('/dates/books/2006/make_object_list/')
         self.assertEqual(res.status_code, 200)
-        self.assertEqual(list(res.context['date_list']), [datetime.datetime(2006, 5, 1)])
+        self.assertEqual(list(res.context['date_list']), [datetime.date(2006, 5, 1)])
         self.assertEqual(list(res.context['book_list']), list(Book.objects.filter(pubdate__year=2006)))
         self.assertEqual(list(res.context['object_list']), list(Book.objects.filter(pubdate__year=2006)))
         self.assertTemplateUsed(res, 'generic_views/book_archive_year.html')
@@ -181,7 +182,7 @@ class YearArchiveViewTests(TestCase):
 
         res = self.client.get('/dates/books/%s/allow_future/' % year)
         self.assertEqual(res.status_code, 200)
-        self.assertEqual(list(res.context['date_list']), [datetime.datetime(year, 1, 1)])
+        self.assertEqual(list(res.context['date_list']), [datetime.date(year, 1, 1)])
 
     def test_year_view_paginated(self):
         res = self.client.get('/dates/books/2006/paginated/')
@@ -204,6 +205,7 @@ class YearArchiveViewTests(TestCase):
         res = self.client.get('/dates/booksignings/2008/')
         self.assertEqual(res.status_code, 200)
 
+    @skipUnlessDBFeature('has_zoneinfo_database')
     @override_settings(USE_TZ=True, TIME_ZONE='Africa/Nairobi')
     def test_aware_datetime_year_view(self):
         BookSigning.objects.create(event_date=datetime.datetime(2008, 4, 2, 12, 0, tzinfo=timezone.utc))
@@ -225,7 +227,7 @@ class MonthArchiveViewTests(TestCase):
         res = self.client.get('/dates/books/2008/oct/')
         self.assertEqual(res.status_code, 200)
         self.assertTemplateUsed(res, 'generic_views/book_archive_month.html')
-        self.assertEqual(list(res.context['date_list']), [datetime.datetime(2008, 10, 1)])
+        self.assertEqual(list(res.context['date_list']), [datetime.date(2008, 10, 1)])
         self.assertEqual(list(res.context['book_list']),
                          list(Book.objects.filter(pubdate=datetime.date(2008, 10, 1))))
         self.assertEqual(res.context['month'], datetime.date(2008, 10, 1))
@@ -268,7 +270,7 @@ class MonthArchiveViewTests(TestCase):
         # allow_future = True, valid future month
         res = self.client.get('/dates/books/%s/allow_future/' % urlbit)
         self.assertEqual(res.status_code, 200)
-        self.assertEqual(res.context['date_list'][0].date(), b.pubdate)
+        self.assertEqual(res.context['date_list'][0], b.pubdate)
         self.assertEqual(list(res.context['book_list']), [b])
         self.assertEqual(res.context['month'], future)
 
@@ -328,6 +330,7 @@ class MonthArchiveViewTests(TestCase):
         res = self.client.get('/dates/booksignings/2008/apr/')
         self.assertEqual(res.status_code, 200)
 
+    @skipUnlessDBFeature('has_zoneinfo_database')
     @override_settings(USE_TZ=True, TIME_ZONE='Africa/Nairobi')
     def test_aware_datetime_month_view(self):
         BookSigning.objects.create(event_date=datetime.datetime(2008, 2, 1, 12, 0, tzinfo=timezone.utc))
diff --git a/tests/regressiontests/model_inheritance_regress/tests.py b/tests/regressiontests/model_inheritance_regress/tests.py
index 6855d70071..8f741bbb7f 100644
--- a/tests/regressiontests/model_inheritance_regress/tests.py
+++ b/tests/regressiontests/model_inheritance_regress/tests.py
@@ -134,8 +134,8 @@ class ModelInheritanceTest(TestCase):
         obj = Child.objects.create(
             name='child',
             created=datetime.datetime(2008, 6, 26, 17, 0, 0))
-        dates = list(Child.objects.dates('created', 'month'))
-        self.assertEqual(dates, [datetime.datetime(2008, 6, 1, 0, 0)])
+        datetimes = list(Child.objects.datetimes('created', 'month'))
+        self.assertEqual(datetimes, [datetime.datetime(2008, 6, 1, 0, 0)])
 
     def test_issue_7276(self):
         # Regression test for #7276: calling delete() on a model with
diff --git a/tests/regressiontests/null_queries/models.py b/tests/regressiontests/null_queries/models.py
index 25560fbab7..9070dd4873 100644
--- a/tests/regressiontests/null_queries/models.py
+++ b/tests/regressiontests/null_queries/models.py
@@ -28,4 +28,5 @@ class OuterB(models.Model):
 
 class Inner(models.Model):
     first = models.ForeignKey(OuterA)
-    second = models.ForeignKey(OuterB, null=True)
+    # second would clash with the __second lookup.
+    third = models.ForeignKey(OuterB, null=True)
diff --git a/tests/regressiontests/null_queries/tests.py b/tests/regressiontests/null_queries/tests.py
index 47c99fbcb3..93e72d55d8 100644
--- a/tests/regressiontests/null_queries/tests.py
+++ b/tests/regressiontests/null_queries/tests.py
@@ -55,17 +55,17 @@ class NullQueriesTests(TestCase):
         """
         obj = OuterA.objects.create()
         self.assertQuerysetEqual(
-            OuterA.objects.filter(inner__second=None),
+            OuterA.objects.filter(inner__third=None),
             ['<OuterA: OuterA object>']
         )
         self.assertQuerysetEqual(
-            OuterA.objects.filter(inner__second__data=None),
+            OuterA.objects.filter(inner__third__data=None),
             ['<OuterA: OuterA object>']
         )
 
         inner_obj = Inner.objects.create(first=obj)
         self.assertQuerysetEqual(
-            Inner.objects.filter(first__inner__second=None),
+            Inner.objects.filter(first__inner__third=None),
             ['<Inner: Inner object>']
         )
 
diff --git a/tests/regressiontests/queries/tests.py b/tests/regressiontests/queries/tests.py
index 9d223970a0..ea54d18451 100644
--- a/tests/regressiontests/queries/tests.py
+++ b/tests/regressiontests/queries/tests.py
@@ -550,37 +550,37 @@ class Queries1Tests(BaseQuerysetTest):
     def test_tickets_6180_6203(self):
         # Dates with limits and/or counts
         self.assertEqual(Item.objects.count(), 4)
-        self.assertEqual(Item.objects.dates('created', 'month').count(), 1)
-        self.assertEqual(Item.objects.dates('created', 'day').count(), 2)
-        self.assertEqual(len(Item.objects.dates('created', 'day')), 2)
-        self.assertEqual(Item.objects.dates('created', 'day')[0], datetime.datetime(2007, 12, 19, 0, 0))
+        self.assertEqual(Item.objects.datetimes('created', 'month').count(), 1)
+        self.assertEqual(Item.objects.datetimes('created', 'day').count(), 2)
+        self.assertEqual(len(Item.objects.datetimes('created', 'day')), 2)
+        self.assertEqual(Item.objects.datetimes('created', 'day')[0], datetime.datetime(2007, 12, 19, 0, 0))
 
     def test_tickets_7087_12242(self):
         # Dates with extra select columns
         self.assertQuerysetEqual(
-            Item.objects.dates('created', 'day').extra(select={'a': 1}),
+            Item.objects.datetimes('created', 'day').extra(select={'a': 1}),
             ['datetime.datetime(2007, 12, 19, 0, 0)', 'datetime.datetime(2007, 12, 20, 0, 0)']
         )
         self.assertQuerysetEqual(
-            Item.objects.extra(select={'a': 1}).dates('created', 'day'),
+            Item.objects.extra(select={'a': 1}).datetimes('created', 'day'),
             ['datetime.datetime(2007, 12, 19, 0, 0)', 'datetime.datetime(2007, 12, 20, 0, 0)']
         )
 
         name="one"
         self.assertQuerysetEqual(
-            Item.objects.dates('created', 'day').extra(where=['name=%s'], params=[name]),
+            Item.objects.datetimes('created', 'day').extra(where=['name=%s'], params=[name]),
             ['datetime.datetime(2007, 12, 19, 0, 0)']
         )
 
         self.assertQuerysetEqual(
-            Item.objects.extra(where=['name=%s'], params=[name]).dates('created', 'day'),
+            Item.objects.extra(where=['name=%s'], params=[name]).datetimes('created', 'day'),
             ['datetime.datetime(2007, 12, 19, 0, 0)']
         )
 
     def test_ticket7155(self):
         # Nullable dates
         self.assertQuerysetEqual(
-            Item.objects.dates('modified', 'day'),
+            Item.objects.datetimes('modified', 'day'),
             ['datetime.datetime(2007, 12, 19, 0, 0)']
         )
 
@@ -699,7 +699,7 @@ class Queries1Tests(BaseQuerysetTest):
         )
 
         # Pickling of DateQuerySets used to fail
-        qs = Item.objects.dates('created', 'month')
+        qs = Item.objects.datetimes('created', 'month')
         _ = pickle.loads(pickle.dumps(qs))
 
     def test_ticket9997(self):
@@ -1235,8 +1235,8 @@ class Queries3Tests(BaseQuerysetTest):
         # field
         self.assertRaisesMessage(
             AssertionError,
-            "'name' isn't a DateField.",
-            Item.objects.dates, 'name', 'month'
+            "'name' isn't a DateTimeField.",
+            Item.objects.datetimes, 'name', 'month'
         )
 
 class Queries4Tests(BaseQuerysetTest):