django url

url django

## how would i make this url more robust?
    url(r'^$',
        'job.list_detail.object_list',
        {
            'queryset': Job.objects.all(),   ## how do i make this robust?  right now if the database is empty i get an error
        },
        name='job_slug_index'),

##here is the error:

DatabaseError at /timelog/

(1054, "Unknown column 'timelog_timelog.' in 'field list'")

Request Method:   GET
Request URL: 	http://localhost:8000/timelog/
Django Version: 	1.4.3
Exception Type: 	DatabaseError
Exception Value: 	

(1054, "Unknown column 'timelog_timelog.client' in 'field list'")


### here is the model 
class Log(models.Model):
    """Represents a time logger system"""
    
    begin_sec = models.DateTimeField( auto_now_add=False,)
    end_sec= models.DateTimeField(  auto_now_add=False,)
    job = models.CharField(max_length=255)  
    assigner = models.CharField(max_length=100)
    client= models.IntegerField(choices=MY_CATEGORIES)
    name = models.IntegerField(choices=MY_SUBCATEGORIES)
    

## and the model form: 

class LogForm(forms.ModelForm):
    """ this handles the start_time and end_time defaults"""
    class Meta: 
        exclude = ['slug','begin_sec']
        model = Job
 
    def __init__(self, *args, **kw):
        super(LogForm).__init__(self, *args, **kw)
   
    def save(self,user, *args, **kw):
        instance = super(JobForm, self).save(commit=False)
        last_entry = Job.objects.aggregate(max_end_sec=models.Max('end_sec'))['max_end_time']
        if last_entry:
            instance.begin_sec = last_entry.end_sec
        else:
            #if this is the very first record pass
            pass
        instance.save()
        return instance

##here are my choices:

MY_CATEGORIES = (
    ('1', 'two'),
    ('2', 'one'),
)