Django model instances primary keys do not reset to 1 after all instances are deleted

by

I wouldn’t call it an issue. This is default behaviour for many database systems. Basically, the auto-increment counter for a table is persistent, and deleting entries does not affect the counter. The actual value of the primary key does not affect performance or anything, it only has aesthetic value (if you ever reach the 2 billion limit you’ll most likely have other problems to worry about).

If you really want to reset the counter, you can drop and recreate the table:

python manage.py sqlclear <app_name> > python manage.py dbshell

Or, if you need to keep the data from other tables in the app, you can manually reset the counter:

python manage.py dbshell
mysql> ALTER TABLE <table_name> AUTO_INCREMENT = 1;

The most probable reason you see different behaviour in your offline and online apps, is that the auto-increment value is only stored in memory, not on disk. It is recalculated as MAX(<column>) + 1 each time the database server is restarted. If the table is empty, it will be completely reset on a restart. This is probably very often for your offline environment, and close to none for your online environment.

More Related Contents:

  1. Django queries – id vs pk
  2. Using a UUID as a primary key in Django models (generic relations impact)
  3. Should I avoid multi-table (concrete) inheritance in Django by any means?
  4. How to define two fields “unique” as couple
  5. How to resolve “django.core.exceptions.ImproperlyConfigured: Application labels aren’t unique, duplicates: foo” in Django 1.7?
  6. How to filter empty or NULL names in a QuerySet?
  7. How to view corresponding SQL query of the Django ORM’s queryset?
  8. In a django model custom save() method, how should you identify a new object?
  9. Unique fields that allow nulls in Django
  10. How to use the request in a ModelForm in Django
  11. Django – iterate number in for loop of a template
  12. Django Static Files Development
  13. How to convert a Django QuerySet to a list?
  14. Tying in to Django Admin’s Model History
  15. django class-based views with inline model-form or formset
  16. Django Template – Increment the value of a variable
  17. How to deploy an HTTPS-only site, with Django/nginx?
  18. Make sure only one worker launches the apscheduler event in a pyramid web app running multiple workers
  19. Django: Validate file type of uploaded file
  20. Django data migration when changing a field to ManyToMany
  21. Django, SESSION_COOKIE_DOMAIN with multiple domains
  22. Organizing Django unit tests
  23. Django templates: value of dictionary key with a space in it
  24. Nginx connection reset, response from uWsgi lost
  25. Log in / Sign up directly on home page
  26. Django’s forms.Form vs forms.ModelForm
  27. How do I set up Jupyter/IPython Notebook for Django?
  28. Having trouble with user.is_authenticated in django template
  29. How to render form field with information that it is required
  30. Forbidden (403) CSRF verification failed. Request aborted

Leave a Comment