id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
2028	Since models do not maintain models.py order , Sqlite code breaks on ForeignKeys	ant9000@…	Adrian Holovaty	"Hello,
I've tried to generate a correct sqlite script for the models.py below:
{{{
from django.db import models
class Device(models.Model):
    pass
class Module(models.Model):
    pass
class Die(models.Model):
    pass
class Wafer(models.Model):
    die_type = models.ForeignKey(Die)
class Padpattern(models.Model):
    pass
class Probecard(models.Model):
    pass
}}}
and it won't work even if Die is defined before Wafer, since the models get reordered.

Here is a quick and dirty patch to django.db.models.loading that makes it work correctly:

{{{
--- loading.py.dist	2006-05-29 09:59:52.078390200 +0200
+++ loading.py	2006-05-29 10:21:42.070052200 +0200
@@ -7,7 +7,10 @@
 
 _app_list = None # Cache of installed apps.
 _app_models = {} # Dictionary of models against app label
-                 # Each value is a dictionary of model name: model class
+                 # Each value is a dictionary with keys 'list', 'dict'
+		  # used to keep track of model name: model class in a sorted fashion
+		  # - 'list' is a sorted list of the models
+		  # - 'dict' associates the model names with their index in 'list'
 
 def get_apps():
     ""Returns a list of all installed modules that contain models.""
@@ -42,7 +45,9 @@
     """"""
     app_list = get_apps() # Run get_apps() to populate the _app_list cache. Slightly hackish.
     if app_mod:
-        return _app_models.get(app_mod.__name__.split('.')[-2], {}).values()
+        model_entry = _app_models.get(app_mod.__name__.split('.')[-2], {})
+	 model_list  = model_entry.setdefault('list',[])
+	 return model_list
     else:
         model_list = []
         for app_mod in app_list:
@@ -56,13 +61,16 @@
     """"""
     get_apps() # Run get_apps() to populate the _app_list cache. Slightly hackish.
     try:
-        model_dict = _app_models[app_label]
+        model_entry = _app_models[app_label]
     except KeyError:
         return None
 
     try:
-        return model_dict[model_name.lower()]
-    except KeyError:
+	 model_dict = model_entry['dict']
+	 model_idx  = model_dict[model_name.lower()]
+	 model_list = model_entry['list']
+        return model_list[model_idx]
+    except KeyError, IndexError:
         return None
 
 def register_models(app_label, *models):
@@ -73,5 +81,8 @@
         # Store as 'name: model' pair in a dictionary
         # in the _app_models dictionary
         model_name = model._meta.object_name.lower()
-        model_dict = _app_models.setdefault(app_label, {})
-        model_dict[model_name] = model
+        model_entry = _app_models.setdefault(app_label, {})
+	 model_list = model_entry.setdefault('list',[])
+	 model_dict = model_entry.setdefault('dict',{})
+	 model_list.append(model)
+	 model_dict[model_name] = len(model_list)-1
}}}

It would probably make sense to implement this hack in a !SortedDict class, and use it as the underlying 
container for modules.

Your software is great, keep on rocking!
Bye,

Ant9000"	defect	closed	Core (Other)	dev	normal	fixed			Unreviewed	0	0	0	0	0	0