diff options
Diffstat (limited to 'lib/sqlalchemy/orm/util.py')
| -rw-r--r-- | lib/sqlalchemy/orm/util.py | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/lib/sqlalchemy/orm/util.py b/lib/sqlalchemy/orm/util.py index 823b97239..66cb2a319 100644 --- a/lib/sqlalchemy/orm/util.py +++ b/lib/sqlalchemy/orm/util.py @@ -839,9 +839,10 @@ class _ORMJoin(expression.Join): # or implicit ON clause, augment it the same way we'd augment the # WHERE. single_crit = right_info.mapper._single_table_criterion - if right_info.is_aliased_class: - single_crit = right_info._adapter.traverse(single_crit) - self.onclause = self.onclause & single_crit + if single_crit is not None: + if right_info.is_aliased_class: + single_crit = right_info._adapter.traverse(single_crit) + self.onclause = self.onclause & single_crit def _splice_into_center(self, other): """Splice a join into the center. |