CODEWITHSUNDEEP
pythondjangodjango-rest-framework
lord stock
lord stock

Reputation: 1201

How do I use update_or_create In django?

I have problem on using update_or_create method in django I have following model

class Search(BaseModel):
    booking_id = models.IntegerField(db_index=True, unique=True)
    trip_type = models.CharField(max_length=20, choices=trip_choice)
    flight_date = models.DateField()
    return_date = models.DateField(null=True, blank=True)

And I tried creating if not exists or update existing value but I am getting integrity error:

duplicate key value violates unique constraint "flight_search_booking_id_key" DETAIL:  Key (booking_id)=(4) already exists.

Here is how I tried saving.

def _save_to_db(self):
    # 14. check if booking id exists previously if exists raise error
    defaults = {'booking_id': 4}

    flight_data, _created = Search.objects.update_or_create(
        booking_id=self._flight_data.get('booking_id'),
        trip_type=self._query_params.get('flight_type'),
        flight_date=self._query_params.get('departure_date'),
        defaults=defaults
    )
    flight_data.save()

I learned default should be provided so I did that too but I am getting error.

Upvotes: 1

Views: 942

Answers (2)

Ashraful Islam
Ashraful Islam

Reputation: 571

   def _save_to_db(self):
        # 14. check if booking id exists previously if exists raise error
        defaults = {'booking_id': 4}

        flight_data, _created = Search.objects.update_or_create(
            booking_id=self._flight_data.get('booking_id',defaults.get("booking_id")),
            trip_type=self._query_params.get('flight_type'),
            flight_date=self._query_params.get('departure_date')
        )
        flight_data.save()

Try it.

Upvotes: 1

diestl
diestl

Reputation: 2058

If your intent is to update the booking with booking_id == 4, then I think this is the correct approach:

def _save_to_db(self):
        # 14. check if booking id exists previously if exists raise error
        defaults = {
            'trip_type': self._query_params.get('flight_type'), 
            'flight_date': self._query_params.get('departure_date'),
            'booking_id': 4,
        }

        flight_data, _created = Search.objects.update_or_create(
            booking_id=self._flight_data.get('booking_id'),
            defaults=defaults
        )
        flight_data.save()

That will update the values of trip_type and flight_date in the Search object with booking_id=4, or create such a Search object otherwise.

Take a look at the django documentation which specifies what the approximate equivalent code is that doesn't use update_or_create: https://docs.djangoproject.com/en/3.2/ref/models/querysets/#django.db.models.query.QuerySet.update_or_create

Upvotes: 1

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