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
10339	models.my_model.objects.get(id=None) returns a result in MySQL	Randy Barlow	nobody	"I stumbled upon an interesting bug today, and I believe that I've narrowed it down to Django's MySQL layer.  When using MySQL, models.my_model.objects.get(id=None) will return a result, when it should raise a DoesNotExist exception.  Here is a very simple example that will reproduce this error.  Suppose you have the following model:

{{{
from django.db import models

class company(models.Model):
    name = models.CharField(max_length=255, unique=True)
    active = models.BooleanField(default=True)
}}}

Here is a shell session that exhibits the behavior I expect, using sqlite3:

{{{
>>> from mysqltest import models
>>> models.company.objects.all()
[]
>>> c = models.company(name='the Company')
>>> c.save()
>>> models.company.objects.all()
[<company: company object>]
>>> models.company.objects.get(id=1)
<company: company object>
>>> models.company.objects.get(id=None)
Traceback (most recent call last):
  File ""<console>"", line 1, in <module>
  File ""//usr/lib/python2.5/site-packages/django/db/models/manager.py"", line 93, in get
    return self.get_query_set().get(*args, **kwargs)
  File ""//usr/lib/python2.5/site-packages/django/db/models/query.py"", line 303, in get
    % self.model._meta.object_name)
DoesNotExist: company matching query does not exist.
}}}

And here is a shell session demonstrating the behavior that MySQL exhibits:

{{{
>>> from mysqltest import models
>>> models.company.objects.all()
[]
>>> c = models.company(name='the Company')
>>> c.save()
>>> models.company.objects.all()
[<company: company object>]
>>> models.company.objects.get(id=1)
<company: company object>
>>> models.company.objects.get(id=None)
<company: company object>
}}}

I have done a little poking around to narrow down whether the problem is in Python's MySQL bindings, or in Django's MySQL layer, and I do believe it is a Django bug.  When I executed the queries (gotten from django.db.connection) directly using python's mysql bindings, the results came back as expected with no results.  I also tried using the mysql shell directly, and also found it to return the expected results (nothing)."		closed	Database layer (models, ORM)	1.0		wontfix	mysql get		Unreviewed	0	0	0	0	0	0