数据必须像

Question

I'm using an external database with Django. I had already written a script to populate the database. I was able to access this data with syncdb, and I have created a model for this data.

I am able to print the entire database, but using:

 TicketOdds.objects.all()[0]

raises the following exception:

ValueError at /

data must be QuerySet-like (have count and order_by) or support list(data) -- TicketOdds has neither

My model is:

class TicketOdds(models.Model):
    #id = models.AutoField(primary_key=True)
    price = models.IntegerField(blank=True, null=True)
    ticket_name = models.TextField(blank=True, null=True)
    ticket_id = models.IntegerField(primary_key=True, blank=True, null=False)
    odds = models.FloatField(blank=True, null=True)
    img_url = models.TextField(blank=True, null=True)
    ticket_url = models.TextField(blank=True, null=True)

    class Meta:
        managed = False
        db_table = 'ticket_odds'

    def __iter__(self):
        for i in xrange(100):
            yield i

    def __getitem__(self):
        return unicode(self)

What do I add to the model to make it "queryset-like"? I tried adding

def __iter__ (self):

for that specific purpose... I must be missing something.

Answer 1

Since you didn't post the full traceback error message. I will just guide you along with the process to answer your question.

1. Look at the source code . It will raise such error when data in the TableData(data, table) is not iterable. ie __iter__ is not defined.
2. I doubt that you need to define the __iter__ methods in your Model or Model.Meta , because QuerySet which is an iterable class can be retrieved when you made this call: TicketOdds.objects.all()
3. Pass the data with the queryset you retrieved previously when you make the TableData(data, table)

Example:

TableData(TicketOdds.objects.all(), table)

What do I add to the model to make it "queryset-like"?

You don't make your model "queryset-like", but rather you get the QuerySet from the models using the above example.