- Added an informative error message when

    ForeignKeyConstraint refers to a column name in
    the parent that is not found.  Also in 0.6.9.
- add tests for [ticket:2226], as if we hit each @declared_attr
directly with obj.__get__(obj, name) instead of using
getattr(cls, name).  Basic inheritance mechanics are improperly
used in this case, so 2226 is invalid.

2 files changed, 7 insertions, 3 deletions

diff --git a/lib/sqlalchemy/ext/declarative.py b/lib/sqlalchemy/ext/declarative.py
index 8c26edf5c..15e7ba34f 100755
--- a/lib/sqlalchemy/ext/declarative.py
+++ b/lib/sqlalchemy/ext/declarative.py
@@ -944,7 +944,6 @@ def _as_declarative(cls, classname, dict_):
                 continue
             elif base is not cls:
                 # we're a mixin.
-
                 if isinstance(obj, Column):
                     if obj.foreign_keys:
                         raise exc.InvalidRequestError(
@@ -1042,7 +1041,6 @@ def _as_declarative(cls, classname, dict_):
             if key == c.key:
                 del our_stuff[key]
     cols = sorted(cols, key=lambda c:c._creation_order)
-
     table = None
     if '__table__' not in dict_:
         if tablename is not None:
diff --git a/lib/sqlalchemy/schema.py b/lib/sqlalchemy/schema.py
index 1763dc484..25c7e30a2 100644
--- a/lib/sqlalchemy/schema.py
+++ b/lib/sqlalchemy/schema.py
@@ -2008,7 +2008,13 @@ class ForeignKeyConstraint(Constraint):
             # string-specified column names now get
             # resolved to Column objects
             if isinstance(col, basestring):
-                col = table.c[col]
+                try:
+                    col = table.c[col]
+                except KeyError:
+                    raise exc.ArgumentError(
+                                "Can't create ForeignKeyConstraint "
+                                "on table '%s': no column "
+                                "named '%s' is present." % (table.description, col))
 
             if not hasattr(fk, 'parent') or \
                 fk.parent is not col: