How to copy django objects from one DB to the other

Sometimes you need  two databases connections to synchronize objects from one django database to the other.


    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': BASE_DIR / 'db.sqlite3',
    'old_db': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': BASE_DIR / 'old_db/db_24.11.2022.sqlite3',


from django.db import models, IntegrityError, DatabaseError
from import BaseCommand
from page.models import *
import sys, traceback

class Command(BaseCommand):
def handle(self, *args, **options):

pages_old = StaticPage.objects.using('old_db').filter(url_source__icontains='', added__gt='2022-11-20') # YYYY-MM-DD
for page in pages_old:'default')

 Django documentation 

!!!!!  Note this way forces the ID and internet database ID to be out of sync

IntegrityError at /admin/VehicleDealerManagement/vehicle/add/

duplicate key value violates unique constraint "VehicleDealerManagement_vehicle_pkey"
DETAIL:  Key (id)=(1) already exists.

See more information about how to fix this problem. 


What is conclusion of this crazy story? 

1. Use python convention for app naming and always use it. 

 An app's name should follow Pep 8 Guidelines, namely it should be short, all-lowercase and not include numbers, dashes, periods, spaces, or special characters. It also, in general, should be the plural of an app's main model, so our posts app would have a main model called Post. Modules should have short, all-lowercase names. Underscores can be used in the module name if it improves readability. Python packages should also have short, all-lowercase names, although the use of underscores is discouraged. So, 1 and 3 are both valid, but 3 would be the recommended approach.

2. Even in development always use correct database Postgresql. Never use sqlite, even in development. Because moving data can sometimes take 1 or two days. 

 To create and use abstraction a postgresql you can use it via pgBounce.. 


SELECT nextval('auth_user_id_seq');
SELECT MAX(id) FROM auth_user;

SELECT setval('auth_user_id_seq', (SELECT MAX(id) FROM auth_user)+1);

SELECT nextval('auth_permission_id_seq');
SELECT MAX(id) FROM auth_permission;

SELECT setval(‘auth_permission_id_seq', (SELECT MAX(id) FROM auth_permission)+1);

SELECT nextval(AccountingPeriod_accountingperiod_id_seq);
SELECT MAX(id) FROM auth_permission;

SELECT MAX(id) FROM AccountingPeriod_accountingperiod;

SELECT MAX(id) FROM  "AccountingPeriod_accountingperiod";
SELECT nextval('"AccountingPeriod_accountingperiod_id_seq"');
SELECT setval('"AccountingPeriod_accountingperiod_id_seq"', (SELECT MAX(id) FROM "AccountingPeriod_accountingperiod")+1);

SELECT MAX(id) FROM  "BankExport_bankexport";
SELECT nextval('"BankExport_bankexport_id_seq"');
SELECT setval('"BankExport_bankexport_id_seq"', (SELECT MAX(id) FROM "BankExport_bankexport")+1);

SELECT MAX(id) FROM  "Document_document";
SELECT nextval('"Document_document_id_seq"');
SELECT setval('"Document_document_id_seq"', (SELECT MAX(id) FROM "Document_document")+1);

SELECT MAX(id) FROM  "Location_location";
SELECT nextval('"Location_location_id_seq"');
SELECT setval('"Location_location_id_seq"', (SELECT MAX(id) FROM "Location_location")+1);

SELECT MAX(id) FROM  "Multiposter_placement";
SELECT nextval('"Multiposter_placement_id_seq"');
SELECT setval('"Multiposter_placement_id_seq"', (SELECT MAX(id) FROM "Multiposter_placement")+1);

SELECT MAX(id) FROM  "PaymentMethod_paymentmethod";
SELECT nextval('"PaymentMethod_paymentmethod_id_seq"');
SELECT setval('"PaymentMethod_paymentmethod_id_seq"', (SELECT MAX(id) FROM "PaymentMethod_paymentmethod")+1);

SELECT MAX(id) FROM  "Transaction_transaction";
SELECT nextval('"Transaction_transaction_id_seq"');
SELECT setval('"Transaction_transaction_id_seq"', (SELECT MAX(id) FROM "Transaction_transaction")+1);

SELECT MAX(id) FROM  "VehicleDealerManagement_vehicle";
SELECT nextval('"VehicleDealerManagement_vehicle_id_seq"');
SELECT setval('"VehicleDealerManagement_vehicle_id_seq"', (SELECT MAX(id) FROM "VehicleDealerManagement_vehicle")+1);

SELECT MAX(id) FROM  "VehicleDealerManagement_vehiclecost";
SELECT nextval('"VehicleDealerManagement_vehiclecost_id_seq"');
SELECT setval('"VehicleDealerManagement_vehiclecost_id_seq"', (SELECT MAX(id) FROM "VehicleDealerManagement_vehiclecost")+1);

SELECT MAX(id) FROM  "VehicleDealerManagement_vehicledocument";
SELECT nextval('"VehicleDealerManagement_vehicledocument_id_seq"');
SELECT setval('"VehicleDealerManagement_vehicledocument_id_seq"', (SELECT MAX(id) FROM "VehicleDealerManagement_vehicledocument")+1);

SELECT MAX(id) FROM  "VehicleDealerManagement_vehicleimage";
SELECT nextval('"VehicleDealerManagement_vehicleimage_id_seq"');
SELECT setval('"VehicleDealerManagement_vehicleimage_id_seq"', (SELECT MAX(id) FROM "VehicleDealerManagement_vehicleimage")+1);

SELECT MAX(id) FROM  "VehicleMerk_vehiclemerk";
SELECT nextval('"VehicleMerk_vehiclemerk_id_seq"');
SELECT setval('"VehicleMerk_vehiclemerk_id_seq"', (SELECT MAX(id) FROM "VehicleMerk_vehiclemerk")+1);

SELECT MAX(id) FROM  "auth_permission_id_seq";
SELECT nextval('"VehicleMerk_vehiclemodel_id_seq"');
SELECT setval('"VehicleMerk_vehiclemodel_id_seq"', (SELECT MAX(id) FROM "VehicleMerk_vehiclemodel")+1);

 Schema |                      Name                      |   Type   |   Owner   
 public | AccountingPeriod_accountingperiod              | table    | quickbook
 public | AccountingPeriod_accountingperiod_id_seq       | sequence | quickbook
 public | BankExport_bankexport                          | table    | quickbook
 public | BankExport_bankexport_id_seq                   | sequence | quickbook
 public | Document_document                              | table    | quickbook
 public | Document_document_id_seq                       | sequence | quickbook
 public | Location_location                              | table    | quickbook
 public | Location_location_id_seq                       | sequence | quickbook
 public | Multiposter_placement                          | table    | quickbook
 public | Multiposter_placement_id_seq                   | sequence | quickbook
 public | PaymentMethod_paymentmethod                    | table    | quickbook
 public | PaymentMethod_paymentmethod_id_seq             | sequence | quickbook
 public | Transaction_transaction                        | table    | quickbook
 public | Transaction_transaction_id_seq                 | sequence | quickbook
 public | VehicleDealerManagement_vehicle                | table    | quickbook
 public | VehicleDealerManagement_vehicle_id_seq         | sequence | quickbook
 public | VehicleDealerManagement_vehiclecost            | table    | quickbook
 public | VehicleDealerManagement_vehiclecost_id_seq     | sequence | quickbook
 public | VehicleDealerManagement_vehicledocument        | table    | quickbook
 public | VehicleDealerManagement_vehicledocument_id_seq | sequence | quickbook
 public | VehicleDealerManagement_vehicleimage           | table    | quickbook
 public | VehicleDealerManagement_vehicleimage_id_seq    | sequence | quickbook
 public | VehicleMerk_vehiclemerk                        | table    | quickbook
 public | VehicleMerk_vehiclemerk_id_seq                 | sequence | quickbook
 public | VehicleMerk_vehiclemodel                       | table    | quickbook
 public | VehicleMerk_vehiclemodel_id_seq                | sequence | quickbook
 public | auth_group                                     | table    | quickbook
 public | auth_group_id_seq                              | sequence | quickbook
 public | auth_group_permissions                         | table    | quickbook
 public | auth_group_permissions_id_seq                  | sequence | quickbook
 public | auth_permission                                | table    | quickbook
 public | auth_permission_id_seq                         | sequence | quickbook
 public | auth_user                                      | table    | quickbook
 public | auth_user_groups                               | table    | quickbook
 public | auth_user_groups_id_seq                        | sequence | quickbook
 public | auth_user_id_seq                               | sequence | quickbook