On 4 Mar, 01:19, Steven Sacks <stevensa...@gmail.com> wrote: > Here is my model: > > class PlaylistTag(models.Model): > playlist = models.ForeignKey(Playlist) > tag = models.CharField(max_length=128) > tag_count = models.PositiveIntegerField(default=1) > > The way this model works is simple. If you add a tag to a playlist, > and the tag doesn't exist, the tag_count is 1. If you add the same tag > again to that playlist, the tag_count is incremented. If you remove > that tag, it is decremented. If it reaches 0, I remove the row > entirely. > > A playlist can have multiple tags and a tag can belong to different > playlists. > > (...) > > Does this make sense?
IMHO - no, that doesn't make sense :-) What you need fior the start - and in fact write about - is: playlists = ManyToManyField(Playlist) and no `tag_count` field, unless you want denormalize your schema - which you probably don't. To count tags for given playlist, you simply do: playlist.playlisttag_set.count() Last but not least, looking at your SQL query it might be that I don't quite get what you need. -- Tomasz Zielinski pyconsultant.eu -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
