From 6678de130c9539d2103b5c72561c0869f0d838d7 Mon Sep 17 00:00:00 2001
From: Malcolm Tredinnick <malcolm.tredinnick@gmail.com>
Date: Sun, 14 Oct 2007 03:46:44 +0000
Subject: [PATCH] queryset-refactor: Fixed handling of extra(tables=...). In
 passing, this solves a duplicate table / bad SQL problem. Refs #2496.

git-svn-id: http://code.djangoproject.com/svn/django/branches/queryset-refactor@6504 bcc190cf-cafb-0310-a4f2-bffc1f526a37
---
 django/db/models/sql/query.py           | 6 +++++-
 tests/regressiontests/queries/models.py | 4 ++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py
index c5c7ee07ee..8914bce15c 100644
--- a/django/db/models/sql/query.py
+++ b/django/db/models/sql/query.py
@@ -371,7 +371,11 @@ class Query(object):
                             qn(lhs_col), qn(alias), qn(col)))
             else:
                 result.append('%s%s' % (qn(name), alias_str))
-        result.extend(self.extra_tables)
+        extra_tables = []
+        for t in self.extra_tables:
+            alias, created = self.table_alias(t)
+            if created:
+                result.append(', %s' % alias)
         return result, []
 
     def get_grouping(self):
diff --git a/tests/regressiontests/queries/models.py b/tests/regressiontests/queries/models.py
index afc70dee9a..64baacc32d 100644
--- a/tests/regressiontests/queries/models.py
+++ b/tests/regressiontests/queries/models.py
@@ -202,5 +202,9 @@ Bug #2400
 [<Author: a3>]
 >>> Tag.objects.filter(item__isnull=True)
 [<Tag: t5>]
+
+Bug #2496
+>>> Item.objects.extra(tables=['queries_author']).select_related().order_by('name')[:1]
+[<Item: four>]
 """}