TransactionManagementError when model has primary_key=True

[youhongshen]

When I tried to add an entry to Zone table, I get the an error message (see below). I have several model classes. It seems like I only get this error if my model has primary_key=True.

model with the problem
class Zone(models.Model):
name = models.CharField(max_length=20, primary_key=True)

def __unicode__(self):
    return '%s' % self.name

error message

Environment:

Request Method: POST
Request URL: http://icbsgps01-dev:8001/admin/inventory/zone/add/

Django Version: 1.8.11
Python Version: 2.7.5
Installed Applications:
('django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.messages',
'django.contrib.sessions',
'django.contrib.staticfiles',
'nested_admin',
'rest_framework',
'rest_framework_extensions',
'papriqa.release_manifest',
'papriqa.sw_validation',
'papriqa.alarm_reg',
'papriqa.inventory',
'import_export',
'session_security',
'simple_audit')
Installed Middleware:
('django.middleware.common.CommonMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.security.SecurityMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware',
'session_security.middleware.SessionSecurityMiddleware',
'simple_audit.middleware.TrackingRequestOnThreadLocalMiddleware')

Traceback:
File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/core/handlers/base.py" in get_response

1.                 response = wrapped_callback(request, _callback_args, *_callback_kwargs)
   

   File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/contrib/admin/options.py" in wrapper

2.             return self.admin_site.admin_view(view)(_args, *_kwargs)
   

   File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/utils/decorators.py" in _wrapped_view

3.                 response = view_func(request, _args, *_kwargs)
   

   File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/views/decorators/cache.py" in _wrapped_view_func

4.     response = view_func(request, _args, *_kwargs)
   

   File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/contrib/admin/sites.py" in inner

5.         return view(request, _args, *_kwargs)
   

   File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/contrib/admin/options.py" in add_view

6.     return self.changeform_view(request, None, form_url, extra_context)
   

   File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/utils/decorators.py" in _wrapper

7.         return bound_func(_args, *_kwargs)
   

   File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/utils/decorators.py" in _wrapped_view

8.                 response = view_func(request, _args, *_kwargs)
   

   File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/utils/decorators.py" in bound_func

9.             return func.**get**(self, type(self))(_args2, *_kwargs2)
   

   File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/utils/decorators.py" in inner

10.                 return func(_args, *_kwargs)
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/contrib/admin/options.py" in changeform_view

11.             self.save_model(request, new_object, form, not add)
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/contrib/admin/options.py" in save_model

12.     obj.save()
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/db/models/base.py" in save

13.                    force_update=force_update, update_fields=update_fields)
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/db/models/base.py" in save_base

14.         updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/db/models/base.py" in _save_table

15.                                   forced_update)
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/db/models/base.py" in _do_update

16.         return update_fields is not None or filtered.exists()
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/db/models/query.py" in exists

17.         return self.query.has_results(using=self.db)
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/db/models/sql/query.py" in has_results

18.     return compiler.has_results()
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/db/models/sql/compiler.py" in has_results

19.     return bool(self.execute_sql(SINGLE))
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/db/models/sql/compiler.py" in execute_sql

20.         cursor.execute(sql, params)
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/db/backends/utils.py" in execute

21.         return super(CursorDebugWrapper, self).execute(sql, params)
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/db/backends/utils.py" in execute

22.     self.db.validate_no_broken_transaction()
    

    File "/home/npacadm/joan_env2/lib/python2.7/site-packages/django/db/backends/base/base.py" in validate_no_broken_transaction

23.             "An error occurred in the current transaction. You can't "
    

Exception Type: TransactionManagementError at /admin/inventory/zone/add/
Exception Value: An error occurred in the current transaction. You can't execute queries until the end of the 'atomic' block.