{{{
 ---
 ObjIsA:
   columns:
     obj_id:
       type: integer(20)
       primary: true
     isa_obj_id:
       type: integer(20)
       primary: true

 Obj:
   columns:
     name: string(255)
     value: object
   relations:
     IsA:
       class: Obj
       refClass: ObjIsA
       local: obj_id
       foreign: isa_obj_id

 ObjClass:
   inheritance:
     extends: Obj
     type: column_aggregation
     keyField: type
     keyValue: 1
   relations:
     Holds:
       class: Obj
       refClass: ObjIsA
       local: isa_obj_id
       foreign: obj_id

 ObjInstance:
   inheritance:
     extends: Obj
     type: column_aggregation
     keyField: type
     keyValue: 2
 }}}
 fixtures:
 {{{
 ---
 Obj:
   car:
     type: 1
     name: Car
   bmw1:
     name: BMW 1
     type: 2
     IsA: [car]
   pp:
     name: Peugeot Partner
     type: 2
     IsA: [car]
 }}}

 Retrieving objects using one query to get both the object and the IsA
 correctly returns all related objects:
 {{{
 $obj = Doctrine::getTable('Obj')
       ->createQuery('a')
       ->addWhere('a.name = ?','BMW 1')
       ->addFrom('a.IsA i')
       ->execute();
 }}}
 returns:
 {{{
 $obj->toArray(): Array
 (
     [id] => 2
     [name] => BMW 1
     [value] =>
     [type] => 2
     [IsA] => Array
         (
             [0] => Array
                 (
                     [id] => 1
                     [name] => Car
                     [value] =>
                     [type] => 1
                     [IsA] => Array
                         (
                         )
                 )
         )
 )
 }}}

 Indirect retrieval fails though:
 {{{
 $obj = Doctrine::getTable('Obj')->findOneByName('BMW 1');
 $temp = $obj['IsA'];
 }}}
 obj now holds:
 {{{
 $obj->toArray(): Array
 (
     [id] => 2
     [name] => BMW 1
     [value] =>
     [type] => 2
     [IsA] => Array
         (
         )
 )
 }}}
 Note that no related IsA records are found.

 Problem is that the produced query inserts a where clause demanding that
 all related objects should be the same aggregation type (type==2). This is
 wrong, as the relation is defined on Obj objects, which can have any type
 value. Correct behaviour would be to not insert any constraints on the Obj
 objects.

 The produced SQL: (copied from debug panel in symfony)
 {{{
 SELECT o.id AS o__id, o.name AS o__name, o.value AS o__value, o.type AS
 o__type FROM obj o WHERE o.name = ? LIMIT 1 - (BMW 1 )

 SELECT obj.id AS obj__id, obj.name AS obj__name, obj.value AS obj__value,
 obj.type AS obj__type, obj_is_a.obj_id AS obj_is_a__obj_id,
 obj_is_a.isa_obj_id AS obj_is_a__isa_obj_id FROM obj INNER JOIN obj_is_a
 ON obj.id = obj_is_a.isa_obj_id WHERE obj.id IN (SELECT isa_obj_id FROM
 obj_is_a WHERE obj_id = ?) AND obj.type = '2' - (2 )
 }}}

 Note the last "AND obj.type = '2'"

 I tried to create a patch but drowned in the source of Doctrine, I
 couldn't find the code for injecting the column-aggregation WHERE
 statement. If directed there, I hope I can help some more.

 Thanks in advance!

  * milestone:  => 1.0.5

Comment(by jwage):

 Search the Doctrine/Query.php and Doctrine/Query/Abstract.php for
 getInheritanceCondition. This will lead you to the code which adds the
 conditions to queries.