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
9371	Fixtures combined with inherited models causing constraint violations/possible double entry of data	terpsquared	nobody	"Using a model descended from the provided User model (as described in http://scottbarnham.com/blog/2008/08/21/extending-the-django-user-model-with-inheritance/), in combination with using a fixture, seems to attempt to load the same data twice, resulting in the following:


{{{
$ python ./manage.py syncdb
Creating table auth_permission
Creating table auth_group
Creating table auth_user
Creating table auth_message
Creating table django_content_type
Creating table django_session
Creating table django_admin_log
Creating table testapp_customuser

You just installed Django's auth system, which means you don't have any superusers defined.
Would you like to create one now? (yes/no): no
Installing index for auth.Permission model
Installing index for auth.Message model
Installing index for admin.LogEntry model
Installing json fixture 'initial_data' from absolute path.
Problem installing fixture 'initial_data.json': Traceback (most recent call last):
  File ""/usr/lib/python2.4/site-packages/django/core/management/commands/loaddata.py"", line 116, in handle
    obj.save()
  File ""/usr/lib/python2.4/site-packages/django/core/serializers/base.py"", line 163, in save
    models.Model.save_base(self.object, raw=True)
  File ""/usr/lib/python2.4/site-packages/django/db/models/base.py"", line 379, in save_base
    result = manager._insert(values, return_id=update_pk)
  File ""/usr/lib/python2.4/site-packages/django/db/models/manager.py"", line 138, in _insert
    return insert_query(self.model, values, **kwargs)
  File ""/usr/lib/python2.4/site-packages/django/db/models/query.py"", line 894, in insert_query
    return query.execute_sql(return_id)
  File ""/usr/lib/python2.4/site-packages/django/db/models/sql/subqueries.py"", line 309, in execute_sql
    cursor = super(InsertQuery, self).execute_sql(None)
  File ""/usr/lib/python2.4/site-packages/django/db/models/sql/query.py"", line 1724, in execute_sql
    cursor.execute(sql, params)
  File ""/usr/lib/python2.4/site-packages/django/db/backends/util.py"", line 19, in execute
    return self.cursor.execute(sql, params)
  File ""/usr/lib/python2.4/site-packages/django/db/backends/sqlite3/base.py"", line 168, in execute
    return Database.Cursor.execute(self, query, params)
IntegrityError: column username is not unique

}}}

Same thing with a postgres db:

{{{
python ./manage.py syncdb
Installing json fixture 'initial_data' from absolute path.
Problem installing fixture 'initial_data.json': Traceback (most recent call last):
  File ""/usr/lib/python2.4/site-packages/django/core/management/commands/loaddata.py"", line 116, in handle
    obj.save()
  File ""/usr/lib/python2.4/site-packages/django/core/serializers/base.py"", line 163, in save
    models.Model.save_base(self.object, raw=True)
  File ""/usr/lib/python2.4/site-packages/django/db/models/base.py"", line 379, in save_base
    result = manager._insert(values, return_id=update_pk)
  File ""/usr/lib/python2.4/site-packages/django/db/models/manager.py"", line 138, in _insert
    return insert_query(self.model, values, **kwargs)
  File ""/usr/lib/python2.4/site-packages/django/db/models/query.py"", line 894, in insert_query
    return query.execute_sql(return_id)
  File ""/usr/lib/python2.4/site-packages/django/db/models/sql/subqueries.py"", line 309, in execute_sql
    cursor = super(InsertQuery, self).execute_sql(None)
  File ""/usr/lib/python2.4/site-packages/django/db/models/sql/query.py"", line 1724, in execute_sql
    cursor.execute(sql, params)
  File ""/usr/lib/python2.4/site-packages/django/db/backends/util.py"", line 19, in execute
    return self.cursor.execute(sql, params)
IntegrityError: duplicate key value violates unique constraint ""testapp_customuser_username_key""

}}}

Note: This does not happen when only one record exists in the fixture data.  The sample data I provide has two unique records that should not clash.

The following is the model definition that seems to not be handled:

{{{
from django.db import models
from django.contrib.auth.models import User, UserManager
from django.utils.translation import ugettext_lazy as _
from datetime import datetime


class Customuser(User):
    username = models.CharField(_('customer id'), max_length=30, unique=True, help_text=_(""Required. 30 characters or fewer. Alphanumeric characters only (letters, digits and underscores).""))
    email_id = models.EmailField(_('e-mail address'), blank=True, null=True, unique=True, db_index=True)
    name = models.CharField(max_length=100, blank=True)
    address_1 = models.CharField(max_length=255, blank=True)
    address_2 = models.CharField(max_length=255, blank=True)
    city = models.CharField(max_length=80, blank=True)
    state = models.CharField(max_length=13, blank=True)
    zipcode = models.CharField(max_length=13, blank=True)
    home_phone = models.CharField(max_length=15, blank=True)
    mobile_phone = models.CharField(max_length=15, blank=True)

    CONTACT_PREFERANCE_CHOICES = (
        ('E', 'E-Mail'),
        ('M', 'Regular Mail'),
        ('P', 'Phone'),
        ('N', 'No contact'),
    )

    contact_method = models.CharField(max_length=1, choices=CONTACT_PREFERANCE_CHOICES, blank=True)
    member_since = models.DateField(blank=True, null=True)
    last_activity = models.DateField(blank=True, null=True)
    point_balance = models.IntegerField(default=0)
    NHRA_member = models.BooleanField(default=False)
    IRL_member = models.BooleanField(default=False)

    def __unicode__(self):
        return u'%s' % self.username

    # Use UserManager to get the create_user method, etc.
    objects = UserManager()
}}}

I have provided a sample app that will reproduce this issue.  Both 1.0 and the latest SVN have this issue."	Bug	closed	Core (Serialization)	1.0	Normal	wontfix		djsnickles@… sorin andre.miras+djangoproject@… carlos.palol@…	Accepted	0	0	0	0	0	0