django-queryset

I have a very standard, basic social application -- with status updates (i.e., posts), and multiple comments per post. Given the following simplified models, is it possible, using Django's ORM, to efficiently retrieve all posts and the latest two comments associated with each post, without performing N+1 queries? (That is, without performing a separate query to get the latest comments for each post on the page.) class Post(models.Model): title = models.CharField(max_length=255) text = models.TextField() class Comment(models.Model): text = models.TextField() post = models.ForeignKey(Post,

I have this weird pagination bug in Django: using object_list as a return of a view, but passing a "paginate_by" argument to it, it's repeating some of the results; Otherwise, if I remove the argument or set as "paginate_by=None", the results are correct. If using pagination, the quantity of results is maintained at a total, so, because there are repeated results, the last results are left out of the list, so they don't appear in the template. Any ideas of what might be happening? Thanks! I had this problem also, but found a solution. The problem was that i sorted the dataset by date. When i

Its day two of my new life with Django, please excuse the simplicity of my question. I have an existing DB table(read-only access) that I have successfully displayed the contents of on a webpage using urls, views, models and all that good stuff. The challenge I have is the table does not contain all the information I need to display. The table contains test results with the columns, sampletime, samplevalue, sampleresult. I need to display different data based on what I calculate from those columns. My end goal is to display this info as a time series graph using flotr . For now Id be happy to

Is there a way to query for subset or superset containment with many-to-many fields? Suppose each Person has a list of birds they want to see, and each Aviary houses a list of birds. How can I make a query to find, for a given Person instance, which Aviaries have every bird on the person's list? And similarly, for a given Person instance, how do I find which Aviaries have only birds on the person's list (but not necessarily all of them). Here are my Django 1.5 models: class Bird(models.Model): name = models.CharField(max_length=255, unique=True) class Aviary(models.Model): name = models

I'm surprised that this question apparently doesn't yet exist. If it does, please help me find it. I want to use annotate (Count) and order_by, but I don't want to count every instance of a related object, only those that meet a certain criteron. To wit, that I might list swallows by the number of green coconuts they have carried: swallow.objects.annotate(num_coconuts=Count('coconuts_carried__husk__color = "green"').order_by('num_coconuts') This should be the right way. swallow.objects.filter( coconuts_carried__husk__color="green" ).annotate( num_coconuts=Count('coconuts_carried') ).order_by(

I'm trying to spit out a django page which lists all entries by the year they were created. So, for example: 2010: Note 4 Note 5 Note 6 2009: Note 1 Note 2 Note 3 It's proving more difficult than I would have expected. The model from which the data comes is below: class Note(models.Model): business = models.ForeignKey(Business) note = models.TextField() created = models.DateTimeField(auto_now_add=True) updated = models.DateTimeField(auto_now=True) class Meta: db_table = 'client_note' @property def note_year(self): return self.created.strftime('%Y') def __unicode__(self): return '%s' % self