Commit b52e4519 authored by Malcolm Tredinnick's avatar Malcolm Tredinnick
Browse files

[1.0.X] Fixed #9406 -- Ensure that each database column is only represented 

once in the "ORDER BY" clause of an SQL statement.

Backport of r9251 from trunk.


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.0.X@9252 bcc190cf-cafb-0310-a4f2-bffc1f526a37
parent 43f6136f

django/db/models/sql/query.py

+17 −7
Original line number Diff line number Diff line
@@ -621,6 +621,12 @@ class Query(object): 
            asc, desc = ORDER_DIR['ASC']

        else:

            asc, desc = ORDER_DIR['DESC']



        # It's possible, due to model inheritance, that normal usage might try

        # to include the same field more than once in the ordering. We track

        # the table/column pairs we use and discard any after the first use.

        processed_pairs = set()



        for field in ordering:

            if field == '?':

                result.append(self.connection.ops.random_function_sql())
@@ -638,7 +644,9 @@ class Query(object): 
                # on verbatim.

                col, order = get_order_dir(field, asc)

                table, col = col.split('.', 1)

                if (table, col) not in processed_pairs:

                    elt = '%s.%s' % (qn(table), col)

                    processed_pairs.add((table, col))

                    if not distinct or elt in select_aliases:

                        result.append('%s %s' % (elt, order))

            elif get_order_dir(field)[0] not in self.extra_select:
@@ -646,7 +654,9 @@ class Query(object): 
                # '-field1__field2__field', etc.

                for table, col, order in self.find_ordering_name(field,

                        self.model._meta, default_order=asc):

                    if (table, col) not in processed_pairs:

                        elt = '%s.%s' % (qn(table), qn2(col))

                        processed_pairs.add((table, col))

                        if distinct and elt not in select_aliases:

                            ordering_aliases.append(elt)

                        result.append('%s %s' % (elt, order))

tests/regressiontests/model_inheritance_regress/models.py

+10 −0
Original line number Diff line number Diff line
@@ -257,4 +257,14 @@ DoesNotExist: ArticleWithAuthor matching query does not exist. 
# without error.

>>> _ = QualityControl.objects.create(headline="Problems in Django", pub_date=datetime.datetime.now(), quality=10, assignee="adrian")



# Ordering should not include any database column more than once (this is most

# likely to ocurr naturally with model inheritance, so we check it here).

# Regression test for #9390. This necessarily pokes at the SQL string for the

# query, since the duplicate problems are only apparent at that late stage.

>>> sql = ArticleWithAuthor.objects.order_by('pub_date', 'pk').query.as_sql()[0]

>>> fragment = sql[sql.find('ORDER BY'):]

>>> pos = fragment.find('pub_date')

>>> fragment.find('pub_date', pos + 1) == -1

True



"""}