Question

I am learning Django and I refer djangobook.com.

I have a model like this:

class Publisher(models.Model):
    name = models.CharField(max_length=30)
    address = models.CharField(max_length=50)
    city = models.CharField(max_length=60)
    state_province = models.CharField(max_length=30)
    country = models.CharField(max_length=50)
    website = models.URLField()

    def __unicode__(self):
        return self.name

I have populated some data (as described in the demo) and tried to update the value of a particular field of a record (as explained) and this works perfectly fine:

>>> publisher_list = Publisher.objects.all()
>>> p = publisher_list[0]
>>> p.name = u'Apress'
>>> p.save()

But when I try the below (which I assume is equivalent to the above), it does not work. The name is not updated in the database. What am I doing wrong here?

>>> publisher_list = Publisher.objects.all()
>>> publisher_list[0].name = 'Apress'
>>> publisher_list[0].save()

Reference: http://djangobook.com/en/2.0/chapter05/

Thanks.

Answer 1

Your indexing is retrieving the model from the database multiple times. Bind the model to a name before mutating and saving it.