python - Using Multiple Databases with django

Question

I have to use multiple databases in my project but there is a problem. Model can't see my database.

when i go localhost:port/admin/app/accounts it says me no such table: accounts. model looking default database. not accounts.db how can i do that?

I tried multiple thins in what i saw in internet but nothing happend.

settings.py :
.....
DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
    },

    'accounts': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': os.path.join(BASE_DIR, 'accounts.db')
    }
}
.....


models.py:
.....
class Accounts(models.Model):     

    email = models.TextField(blank=True, null=True)                                                                                                                    
    phone = models.TextField(blank=True, null=True)                                                                                                                    
    name = models.TextField(blank=True, null=True)                                                                                                                     
    password = models.TextField(blank=True, null=True)                                                                                                                 
    verify = models.IntegerField(blank=True, null=True)                                                                                                                

    class Meta:                                                                                                                                                        
        managed = False

        db_table = 'accounts'
....


Environment:


Request Method: GET
Request URL: http://localhost:port/admin/hede/accounts/

Django Version: 1.11.23
Python Version: 2.7.15
Installed Applications:
['django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'hede']
Installed Middleware:
['django.middleware.security.SecurityMiddleware',
 'django.contrib.sessions.middleware.SessionMiddleware',
 'django.middleware.common.CommonMiddleware',
 'django.middleware.csrf.CsrfViewMiddleware',
 'django.contrib.auth.middleware.AuthenticationMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware',
 'django.middleware.clickjacking.XFrameOptionsMiddleware']



Traceback:

File "/usr/local/lib/python2.7/dist-packages/django/core/handlers/exception.py" in inner
  41.             response = get_response(request)

File "/usr/local/lib/python2.7/dist-packages/django/core/handlers/base.py" in _get_response
  187.                 response = self.process_exception_by_middleware(e, request)

File "/usr/local/lib/python2.7/dist-packages/django/core/handlers/base.py" in _get_response
  185.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)

File "/usr/local/lib/python2.7/dist-packages/django/contrib/admin/options.py" in wrapper
  552.                 return self.admin_site.admin_view(view)(*args, **kwargs)

File "/usr/local/lib/python2.7/dist-packages/django/utils/decorators.py" in _wrapped_view
  149.                     response = view_func(request, *args, **kwargs)

File "/usr/local/lib/python2.7/dist-packages/django/views/decorators/cache.py" in _wrapped_view_func
  57.         response = view_func(request, *args, **kwargs)

File "/usr/local/lib/python2.7/dist-packages/django/contrib/admin/sites.py" in inner
  224.             return view(request, *args, **kwargs)

File "/usr/local/lib/python2.7/dist-packages/django/utils/decorators.py" in _wrapper
  67.             return bound_func(*args, **kwargs)

File "/usr/local/lib/python2.7/dist-packages/django/utils/decorators.py" in _wrapped_view
  149.                     response = view_func(request, *args, **kwargs)

File "/usr/local/lib/python2.7/dist-packages/django/utils/decorators.py" in bound_func
  63.                 return func.__get__(self, type(self))(*args2, **kwargs2)

File "/usr/local/lib/python2.7/dist-packages/django/contrib/admin/options.py" in changelist_view
  1564.                 self.list_max_show_all, self.list_editable, self,

File "/usr/local/lib/python2.7/dist-packages/django/contrib/admin/views/main.py" in __init__
  79.         self.get_results(request)

File "/usr/local/lib/python2.7/dist-packages/django/contrib/admin/views/main.py" in get_results
  177.         result_count = paginator.count

File "/usr/local/lib/python2.7/dist-packages/django/utils/functional.py" in __get__
  35.         res = instance.__dict__[self.name] = self.func(instance)

File "/usr/local/lib/python2.7/dist-packages/django/core/paginator.py" in count
  79.             return self.object_list.count()

File "/usr/local/lib/python2.7/dist-packages/django/db/models/query.py" in count
  364.         return self.query.get_count(using=self.db)

File "/usr/local/lib/python2.7/dist-packages/django/db/models/sql/query.py" in get_count
  499.         number = obj.get_aggregation(using, ['__count'])['__count']

File "/usr/local/lib/python2.7/dist-packages/django/db/models/sql/query.py" in get_aggregation
  480.         result = compiler.execute_sql(SINGLE)

File "/usr/local/lib/python2.7/dist-packages/django/db/models/sql/compiler.py" in execute_sql
  899.             raise original_exception

Exception Type: OperationalError at /admin/hede/accounts/
Exception Value: no such table: accounts

Answer 1

To use multiple databases you have to tell Django about the database server you will be using, but adding them in the settings.py.

Multiple databases

    'default': {
        'NAME': 'app_data',
        'ENGINE': 'django.db.backends.postgresql',
        'USER': 'postgres_user',
        'PASSWORD': 's3krit'
    },
    'users': {
        'NAME': 'user_data',
        'ENGINE': 'django.db.backends.mysql',
        'USER': 'mysql_user',
        'PASSWORD': 'priv4te'
    }
}

The migrate management command operates on one database at a time. By default, it operates on the default database, but by providing the --database option, you can tell it to synchronize a different database.

$ ./manage.py migrate --database=users
$ ./manage.py migrate --database=customers

You can manually select the database in your queries queries e.g

user = User(....)
user.save(using='users')

Customer.objects.all().using('users')

Using raw cursor

with connections['users'].cursor() as cursor:
     cursor.execute("SELECT * FROM users__users")