Fixed #10109 -- Removed the use of raw SQL in many-to-many fields by introducing an autogenerated through model.

This is the first part of Alex Gaynor's GSoC project to add Multi-db support to Django.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@11710 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/core/serializers/python.py

@@ -56,7 +56,7 @@ class Serializer(base.Serializer):
         self._current[field.name] = smart_unicode(related, strings_only=True)
 
     def handle_m2m_field(self, obj, field):
-        if field.creates_table:
+        if field.rel.through._meta.auto_created:
             self._current[field.name] = [smart_unicode(related._get_pk_val(), strings_only=True)
                                for related in getattr(obj, field.name).iterator()]
 

django/core/serializers/xml_serializer.py

@@ -98,7 +98,7 @@ class Serializer(base.Serializer):
         serialized as references to the object's PK (i.e. the related *data*
         is not dumped, just the relation).
         """
-        if field.creates_table:
+        if field.rel.through._meta.auto_created:
             self._start_relational_field(field)
             for relobj in getattr(obj, field.name).iterator():
                 self.xml.addQuickElement("object", attrs={"pk" : smart_unicode(relobj._get_pk_val())})
@@ -233,4 +233,3 @@ def getInnerText(node):
         else:
            pass
     return u"".join(inner_text)
-