Fixed #8819 -- Don't include two copies of extra-select columns in the query.

This was triggered by r8794, but was, in fact, fairly fragile before then. The
current fix is the correct way we should be doing this.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@8898 bcc190cf-cafb-0310-a4f2-bffc1f526a37

2 files changed, 10 insertions, 1 deletions

diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py
index bd723f69d9..ceaf65cd4d 100644
--- a/django/db/models/sql/query.py
+++ b/django/db/models/sql/query.py
@@ -630,7 +630,7 @@ class Query(object):
             else:
                 col, order = get_order_dir(field, asc)
                 elt = qn2(col)
-                if distinct and elt not in select_aliases:
+                if distinct and col not in select_aliases:
                     ordering_aliases.append(elt)
                 result.append('%s %s' % (elt, order))
         self.ordering_aliases = ordering_aliases
diff --git a/tests/regressiontests/extra_regress/models.py b/tests/regressiontests/extra_regress/models.py
index 8ee06bed32..1d31fb267a 100644
--- a/tests/regressiontests/extra_regress/models.py
+++ b/tests/regressiontests/extra_regress/models.py
@@ -98,4 +98,13 @@ True
 >>> Order.objects.extra(where=["username=%s"], params=["fred"], tables=["auth_user"]).order_by('created_by')
 []
 
+# Regression test for #8819: Fields in the extra(select=...) list should be
+# available to extra(order_by=...).
+>>> User.objects.extra(select={'extra_field': 1}).distinct()
+[<User: fred>]
+>>> User.objects.extra(select={'extra_field': 1}, order_by=['extra_field'])
+[<User: fred>]
+>>> User.objects.extra(select={'extra_field': 1}, order_by=['extra_field']).distinct()
+[<User: fred>]
+
 """}