magic-removal: Fixed #1685 -- order_by no longer breaks when using a …

…custom 'select'. Thanks, feiyu.xie

git-svn-id: http://code.djangoproject.com/svn/django/branches/magic-removal@2803 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/models/query.py

@@ -427,7 +427,7 @@ def _get_sql_clause(self):
                 else:
                     # Use the database table as a column prefix if it wasn't given,
                     # and if the requested column isn't a custom SELECT.
-                    if "." not in col_name and col_name not in [k[0] for k in (self._select or ())]:
+                    if "." not in col_name and col_name not in (self._select or ()):
                         table_prefix = backend.quote_name(opts.db_table) + '.'
                     else:
                         table_prefix = ''