Hello World, Welcome to ProjectsPlaza.com. Today we will discuss how to use annotate aggregation in Django. In this tutorial, we will fetch data from two different models. For example, I am creating a video sharing website like YouTube. I have two models. One is a channel and another is a video. Both models are joined with foreign keys. Now I want to fetch channels with videos count. I will do this with annotate aggregation.
# Channel class VideoChannel(models.Model): user=models.ForeignKey(User,on_delete=models.CASCADE) name=models.CharField(max_length=200) detail=models.TextField() def __str__(self): return self.name
# Videos class Video(models.Model): user=models.ForeignKey(User,on_delete=models.CASCADE) channel=models.ForeignKey(VideoChannel,on_delete=models.CASCADE,null=True) src=models.FileField(upload_to='videos/') title=models.CharField(max_length=200,help_text='Enter Title') def __str__(self): return self.title
Fetch channels with videos count
We want to fetch videos count the same as the following screen.
We can fetch this result with the help of the following code.