From 17ac26272402d9e92dfeb80ad0996eb0e9aff29f Mon Sep 17 00:00:00 2001
From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Fri, 13 Jul 2007 08:12:30 +0000
Subject: [PATCH] - a warning is issued by Mapper when two primary key columns
 of the same name are munged into a single attribute.  this happens frequently
 when mapping to joins (or inheritance).

---
 CHANGES                      |  3 +++
 lib/sqlalchemy/orm/mapper.py |  4 +++-
 test/orm/inheritance.py      |  4 ++--
 test/orm/relationships.py    | 14 +++++++-------
 4 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/CHANGES b/CHANGES
index bd71fe1b1f..94a925cae6 100644
--- a/CHANGES
+++ b/CHANGES
@@ -25,6 +25,9 @@
     - added synchronization to the mapper() construction step, to avoid
       thread collections when pre-existing mappers are compiling in a 
       different thread [ticket:613]
+    - a warning is issued by Mapper when two primary key columns of the
+      same name are munged into a single attribute.  this happens frequently
+      when mapping to joins (or inheritance). 
     - synonym() properties are fully supported by all Query joining/
       with_parent operations [ticket:598]
     - fixed very stupid bug when deleting items with many-to-many
diff --git a/lib/sqlalchemy/orm/mapper.py b/lib/sqlalchemy/orm/mapper.py
index bd5e07b148..375408926f 100644
--- a/lib/sqlalchemy/orm/mapper.py
+++ b/lib/sqlalchemy/orm/mapper.py
@@ -9,7 +9,7 @@ from sqlalchemy import sql_util as sqlutil
 from sqlalchemy.orm import util as mapperutil
 from sqlalchemy.orm import sync
 from sqlalchemy.orm.interfaces import MapperProperty, MapperOption, OperationContext, SynonymProperty
-import weakref
+import weakref, warnings
 
 __all__ = ['Mapper', 'MapperExtension', 'class_mapper', 'object_mapper', 'EXT_PASS', 'mapper_registry', 'ExtensionOption']
 
@@ -585,6 +585,8 @@ class Mapper(object):
                     prop = ColumnProperty(deferred=prop.deferred, group=prop.group, *prop.columns)
                     prop.set_parent(self)
                     self.__props[column_key] = prop
+                if column in self.primary_key and prop.columns[-1] in self.primary_key:
+                    warnings.warn(RuntimeWarning("On mapper %s, primary key column '%s' is being combined with distinct primary key column '%s' in attribute '%s'.  Use explicit properties to give each column its own mapped attribute name." % (str(self), str(column), str(prop.columns[-1]), column_key)))
                 prop.columns.append(column)
                 self.__log("appending to existing ColumnProperty %s" % (column_key))
             else:
diff --git a/test/orm/inheritance.py b/test/orm/inheritance.py
index 8d12250887..0458716e5a 100644
--- a/test/orm/inheritance.py
+++ b/test/orm/inheritance.py
@@ -427,7 +427,7 @@ class InheritTest7(testbase.ORMTest):
                 'roles' : relation(Role, secondary=user_roles, lazy=False, private=False) 
             }
         )
-        admin_mapper = mapper(Admin, admins, inherits=user_mapper)
+        admin_mapper = mapper(Admin, admins, inherits=user_mapper, properties={'aid':admins.c.id})
         sess = create_session()
         adminrole = Role('admin')
         sess.save(adminrole)
@@ -463,7 +463,7 @@ class InheritTest7(testbase.ORMTest):
             }
         )
 
-        admin_mapper = mapper(Admin, admins, inherits=user_mapper) 
+        admin_mapper = mapper(Admin, admins, inherits=user_mapper, properties={'aid':admins.c.id}) 
 
         # create roles
         adminrole = Role('admin')
diff --git a/test/orm/relationships.py b/test/orm/relationships.py
index 6f652e692e..7c9bbc8987 100644
--- a/test/orm/relationships.py
+++ b/test/orm/relationships.py
@@ -559,19 +559,19 @@ class TypeMatchTest(testbase.ORMTest):
     def define_tables(self, metadata):
         global a, b, c, d
         a = Table("a", metadata, 
-            Column('id', Integer, primary_key=True),
+            Column('aid', Integer, primary_key=True),
             Column('data', String(30)))
         b = Table("b", metadata, 
-            Column('id', Integer, primary_key=True),
-            Column("a_id", Integer, ForeignKey("a.id")),
+            Column('bid', Integer, primary_key=True),
+            Column("a_id", Integer, ForeignKey("a.aid")),
             Column('data', String(30)))
         c = Table("c", metadata, 
-            Column('id', Integer, primary_key=True),
-            Column("b_id", Integer, ForeignKey("b.id")),
+            Column('cid', Integer, primary_key=True),
+            Column("b_id", Integer, ForeignKey("b.bid")),
             Column('data', String(30)))
         d = Table("d", metadata, 
-            Column('id', Integer, primary_key=True),
-            Column("a_id", Integer, ForeignKey("a.id")),
+            Column('did', Integer, primary_key=True),
+            Column("a_id", Integer, ForeignKey("a.aid")),
             Column('data', String(30)))
     def test_o2m_oncascade(self):
         class A(object):pass
-- 
2.47.2