[1.0.X] Fixed #3501 -- Fixed date filtering in querysets for nullable date fields. Only affects SQLite.

Backport of r9466 from trunk.


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.0.X@9468 bcc190cf-cafb-0310-a4f2-bffc1f526a37

1 files changed, 4 insertions, 2 deletions

diff --git a/django/db/backends/sqlite3/base.py b/django/db/backends/sqlite3/base.py
index f175bc4cb7..745f9982a0 100644
--- a/django/db/backends/sqlite3/base.py
+++ b/django/db/backends/sqlite3/base.py
@@ -101,7 +101,7 @@ class DatabaseOperations(BaseDatabaseOperations):
         return [first % value, second % value]
 
 class DatabaseWrapper(BaseDatabaseWrapper):
-    
+
     # SQLite requires LIKE statements to include an ESCAPE clause if the value
     # being escaped has a percent or underscore in it.
     # See http://www.sqlite.org/lang_expr.html for an explanation.
@@ -124,7 +124,7 @@ class DatabaseWrapper(BaseDatabaseWrapper):
 
     def __init__(self, *args, **kwargs):
         super(DatabaseWrapper, self).__init__(*args, **kwargs)
-        
+
         self.features = DatabaseFeatures()
         self.ops = DatabaseOperations()
         self.client = DatabaseClient()
@@ -179,6 +179,8 @@ class SQLiteCursorWrapper(Database.Cursor):
         return query % tuple("?" * num_params)
 
 def _sqlite_extract(lookup_type, dt):
+    if dt is None:
+        return None
     try:
         dt = util.typecast_timestamp(dt)
     except (ValueError, TypeError):