Django - “wins”列中的空值违反了非空约束

当我尝试在 django 中使用 admin 或通过我的注册功能在视图中创建用户时，它给了我这个错误：

通过注册功能：

IntegrityError at /register_user/
null value in column "wins" violates not-null constraint
DETAIL:  Failing row contains (3, pbkdf2_sha256$36000$3SoR8l6dEXRD$CkFB+RRKeJPUPeux4EByqkYFkGLgkhI..., null, f, Ion, , , [email protected], f, t, 2017-05-08 10:47:39.860612+00, f, null).

通过在管理员中添加用户

IntegrityError at /admin/football_app/customuser/add/
null value in column "wins" violates not-null constraint
DETAIL:  Failing row contains (7, pbkdf2_sha256$36000$o6UGPqAw72hi$qfbgoRAoJn4WmlK010VbfCzeu3+Fo0w..., null, f, Ion, , , , f, t, 2017-05-08 11:02:54.725688+00, f, null).

模型.py

class CustomUser(AbstractUser):
    selected = models.BooleanField(default=False)
    wins = models.IntegerField()
    REQUIRED_FIELDS = ['email', 'selected', 'wins']

    def __str__(self):
        return self.username


class Score(models.Model):
    VALUE = (
        (1, "Score 1"),
        (2, "Score 2"),
        (3, "Score 3"),
        (4, "Score 4"),
        (5, "Score 5"),
        (6, "Score 6"),
        (7, "Score 7"),
        (8, "Score 8"),
        (9, "Score 9"),
        (10, "Score 10"),
    )
    granted_by = models.ForeignKey(settings.AUTH_USER_MODEL, default=0)
    granted_to = models.ForeignKey(settings.AUTH_USER_MODEL, default=0, related_name='granted_to')
    grade = models.PositiveSmallIntegerField(default=0, choices=VALUE)

    def __str__(self):
        return str(self.granted_to)

视图.py

def register_user(request):
    data = dict()
    if request.method == 'POST':
        form = UserForm(request.POST)
        if form.is_valid():
            user = form.save(commit=False)
            user.set_password(user.password)
            user.save()
            return redirect('/login/')
    else:
        data['form'] = UserForm()
    return render(request, 'register_user.html', data)

我正在使用 wins 字段将 +1 添加到用户，并且我正在视图中的其他函数中执行此操作：

User.objects.filter(username__in=data['d1']).update(wins=F('wins') + 1)