how to reset id whenever a row deleted in django? - django

Question

I wanted to start id from 1 whenever a row is deleted it skips that number and jumps to the following number.
like in this image it skips numbers from 1-6 and 8.
I want to set it as 1,2,3.
Here is my models.py module
class dish(models.Model):
id = models.AutoField(primary_key=True)
dish_id = models.AutoField
dish_name = models.CharField(max_length=255, blank=True, null=True)
dish_category = models.CharField(max_length=255, blank=True, null=True)
dish_size = models.CharField(max_length=7, blank=True, null=True)
dish_price = models.IntegerField(blank=True, null=True)
dish_description = models.CharField(max_length=255, blank=True, null=True)
# dish_image = models.ImageField(upload_to="images/", default=None, blank=True, null=True)
dish_image = models.ImageField(upload_to="media/", default=None, blank=True, null=True) #here added images as a foldername to upload to.
dish_date = models.DateField()
def __str__(self):
return self.dish_name
Here is views.py module:
def delete(request, id):
dishs = dish.objects.get(id=id)
dishs.delete()
return HttpResponseRedirect(reverse('check'))

Answer 1

Deleting an object does not change any property of the remaining objects. You need to do that manually. First thing you need to do is to change the dish_id field:
# Change this:
# dish_id = models.AutoField
# to this:
dish_id = models.IntegerField(default=0)
Then in your views:
def delete(request, id):
dishs = dish.objects.get(id=id)
dishs.delete()
all_dishes = dish.objects.all()
for i, dish in enumerate(all_dishes):
dish.dish_id = i + 1
dish.save()
return HttpResponseRedirect(reverse('check'))
Separately, you really should write your classes in Pascal case, capitalizing the first letter of the class:
class Dish(models.Model):
And finally, Dish does not need an id field; that is created automatically, but you can leave that as is, it is not causing any problems.

Answer 2

You can achieve those things using an overriding save() method like this
class dish(models.Model):
id =models.AutoField(primary_key=True)
dish_id = models.BigIntegerField(unique = True)
dish_name = models.CharField(max_length=255, blank=True, null=True)
dish_category = models.CharField(max_length=255, blank=True, null=True)
dish_size = models.CharField(max_length=7, blank=True, null=True)
dish_price = models.IntegerField(blank=True, null=True)
dish_description = models.CharField(max_length=255, blank=True, null=True)
dish_image = models.ImageField(upload_to="images/", default=None, blank=True, null=True)
dish_image = models.ImageField(upload_to="media/", default=None, blank=True, null=True) #here added images as a foldername to upload to.
dish_date = models.DateField()
def __str__(self):
return self.dish_name
def save(self, *args, **kwargs):
count_obj = dish.objects.all().count()+1
self.dish_id = count_obj
super(dish, self).save(*args, **kwargs)