IntegrityError Django ForeignKey sets to none

Question

I've been having an issue with setting the ForeignKey in one of my model fields for the author variable. See below:


class BugTracker(models.Model):
    project_number= models.IntegerField(primary_key=True)
    assignee=  models.ForeignKey(Developer, on_delete=models.CASCADE)
    priority = models.CharField(max_length=10, choices=priority_choices)
    summary=models.TextField()
    status= models.CharField(max_length=20, choices=progress)
    author = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
    created_at=models.DateTimeField(default=timezone.now)
    updated_at=models.DateTimeField(auto_now=True)
   
    def __str__(self):
        return self.summary

    def get_absolute_url(self): 
        return reverse("bug_list")


"IntegrityError at /projects/create/
NOT NULL constraint failed: core_bugtracker.author_id
Request Method: POST
Request URL:    http://127.0.0.1:8000/projects/create/
Django Version: 4.1.5
Exception Type: IntegrityError
Exception Value:    
NOT NULL constraint failed: core_bugtracker.author_id"

As soon as I add "null=True" to the ForeignKey Field, it works and I don't get an error, but the template shows my variable ({bug.author}} equal to "None" regardless of who I'm signed in as. I tried deleting my database and migration files multiple times, but it still doesn't work.

Does this answer your question? ['NOT NULL constraint failed' after adding to models.py](https://stackoverflow.com/questions/25964312/not-null-constraint-failed-after-adding-to-models-py) — Sunderam Dubey, Jan 31 '23 at 02:15

Tevin Joseph K O · Accepted Answer · 2023-01-31T09:43:35.080

1

If you are not passing "author" as a field while saving BugTracker model, you'll get ({bug.author}} as None, because you have set "null=True" in the "author" field declaration - This means you can save BugTracker model without passing an 'author' field and it defaults to null/None.

If you want to set/add an author object to bug_tracker_object, you can do the following. (Note: bug_tracker_object is the BugTracker object that you've populated using fields such as project_number, assignee, priority etc.)

author_object = Author.objects.get(id=<your_author_id>)
bug_tracker_object.author_object = author_object 
bug_tracker_object.save()

edited Jan 31 '23 at 09:43

answered Jan 31 '23 at 09:00

Tevin Joseph K O

2,574
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1

Thank you. I realized that my create view did not set the form instance to to the user: def form_valid(self, form): form.instance.author=self.request.user return super().form_valid(form) – Victor Calimano Feb 01 '23 at 01:23

IntegrityError Django ForeignKey sets to none

1 Answers1