From 7d39ad95d8912816713a822ec2b0954102af6e57 Mon Sep 17 00:00:00 2001
From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Thu, 31 Aug 2006 23:39:42 +0000
Subject: [PATCH] defaults and constraints have optional parent

---
 lib/sqlalchemy/schema.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/sqlalchemy/schema.py b/lib/sqlalchemy/schema.py
index 6fc10c6cb1..5c7ec72b6c 100644
--- a/lib/sqlalchemy/schema.py
+++ b/lib/sqlalchemy/schema.py
@@ -600,7 +600,7 @@ class DefaultGenerator(SchemaItem):
         except AttributeError:
             return self._metadata
     def _get_parent(self):
-        return self.column
+        return getattr(self, 'column', None)
     def _set_parent(self, column):
         self.column = column
         self._metadata = self.column.table.metadata
@@ -687,7 +687,7 @@ class Constraint(SchemaItem):
     def copy(self):
         raise NotImplementedError()
     def _get_parent(self):
-        return self.table
+        return getattr(self, 'table', None)
         
 class ForeignKeyConstraint(Constraint):
     """table-level foreign key constraint, represents a colleciton of ForeignKey objects."""
-- 
2.47.2