1 files changed, 39 insertions, 9 deletions
diff --git a/django/db/models/sql/subqueries.py b/django/db/models/sql/subqueries.py
index 6072804697..6aac5c898c 100644
--- a/django/db/models/sql/subqueries.py
+++ b/django/db/models/sql/subqueries.py
@@ -2,22 +2,23 @@
 Query subclasses which provide extra functionality beyond simple data retrieval.
 """
 
+from django.conf import settings
 from django.core.exceptions import FieldError
 from django.db import connections
 from django.db.models.constants import LOOKUP_SEP
-from django.db.models.fields import DateField, FieldDoesNotExist
+from django.db.models.fields import DateField, DateTimeField, FieldDoesNotExist
 from django.db.models.sql.constants import *
-from django.db.models.sql.datastructures import Date
+from django.db.models.sql.datastructures import Date, DateTime
 from django.db.models.sql.query import Query
 from django.db.models.sql.where import AND, Constraint
-from django.utils.datastructures import SortedDict
 from django.utils.functional import Promise
 from django.utils.encoding import force_text
 from django.utils import six
+from django.utils import timezone
 
 
 __all__ = ['DeleteQuery', 'UpdateQuery', 'InsertQuery', 'DateQuery',
-        'AggregateQuery']
+        'DateTimeQuery', 'AggregateQuery']
 
 class DeleteQuery(Query):
     """
@@ -223,9 +224,9 @@ class DateQuery(Query):
 
     compiler = 'SQLDateCompiler'
 
-    def add_date_select(self, field_name, lookup_type, order='ASC'):
+    def add_select(self, field_name, lookup_type, order='ASC'):
         """
-        Converts the query into a date extraction query.
+        Converts the query into an extraction query.
         """
         try:
             result = self.setup_joins(
@@ -238,10 +239,9 @@ class DateQuery(Query):
                 self.model._meta.object_name, field_name
             ))
         field = result[0]
-        assert isinstance(field, DateField), "%r isn't a DateField." \
-                % field.name
+        self._check_field(field)                # overridden in DateTimeQuery
         alias = result[3][-1]
-        select = Date((alias, field.column), lookup_type)
+        select = self._get_select((alias, field.column), lookup_type)
         self.clear_select_clause()
         self.select = [SelectInfo(select, None)]
         self.distinct = True
@@ -250,6 +250,36 @@ class DateQuery(Query):
         if field.null:
             self.add_filter(("%s__isnull" % field_name, False))
 
+    def _check_field(self, field):
+        assert isinstance(field, DateField), \
+            "%r isn't a DateField." % field.name
+        if settings.USE_TZ:
+            assert not isinstance(field, DateTimeField), \
+                "%r is a DateTimeField, not a DateField." % field.name
+
+    def _get_select(self, col, lookup_type):
+        return Date(col, lookup_type)
+
+class DateTimeQuery(DateQuery):
+    """
+    A DateTimeQuery is like a DateQuery but for a datetime field. If time zone
+    support is active, the tzinfo attribute contains the time zone to use for
+    converting the values before truncating them. Otherwise it's set to None.
+    """
+
+    compiler = 'SQLDateTimeCompiler'
+
+    def _check_field(self, field):
+        assert isinstance(field, DateTimeField), \
+                "%r isn't a DateTimeField." % field.name
+
+    def _get_select(self, col, lookup_type):
+        if self.tzinfo is None:
+            tzname = None
+        else:
+            tzname = timezone._get_timezone_name(self.tzinfo)
+        return DateTime(col, lookup_type, tzname)
+
 class AggregateQuery(Query):
     """
     An AggregateQuery takes another query as a parameter to the FROM