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POAlternative to django concrete inheritance
 

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  1. POAlternative to django concrete inheritance
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    <p>I have a Django model class which encompass various types of model classes like:</p> <pre><code>Content &gt; (Audio, Video, Image) </code></pre> <p>I want to perform queries on this parent model like Content.objects.filter() or Content.objects.recent(). How do i come about this? Presently i am using django's concrete model inheritance, which I suppose impose lot of overheard on the db performance by using joins for the parent classes. I cannot use abstract class because that would not permit me to perform queries on the parent class. Here are my models definitions:</p> <pre><code>class BaseContent(models.Model): """ Concrete base model to encompass all the local and social content. We need a single queryset for all the content on the app. """ title = models.CharField(_('title'), max_length=255, default='') description = models.TextField(_('description'), default='', blank=True) publisher = models.ForeignKey(settings.AUTH_USER_MODEL) allow_comments = models.BooleanField(default=False) is_public = models.BooleanField(default=True) created = AutoCreatedField(_('created')) objects = BaseContentManager() class Video(BaseContent): ACTIVITY_ACTION = 'posted a video' UPLOAD_TO = 'video_files/%Y/%m/%d' PREVIEW_UPLOAD_TO = 'video_frames/%Y/%m/%d' video_file = models.FileField(_('video file'), upload_to=UPLOAD_TO) preview_frame = models.ImageField( _('Preview image'), upload_to=PREVIEW_UPLOAD_TO, blank=True, null=True) category = models.ForeignKey(VideoCategory, blank=True, null=True) num_plays = models.PositiveIntegerField(blank=True, default=0) num_downloads = models.PositiveIntegerField(blank=True, default=0) </code></pre> <p>Thanks in advance.</p>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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