Django filter through multiple fields in a many-to-many intermediary table

Question

I have the following models in my django project:

class Video(models.Model):
    media = models.ForeignKey(Media)

class Media(models.Model):
    title = models.CharField(max_length=255)
    formats = models.ManyToManyField(Format,through='MediaFormat',related_name='media',blank=True)

class Format(models.Model):
    title = models.CharField(max_length=50)

class MediaFormat(models.Model):
    status = models.IntegerField()
    format = models.ForeignKey(Format)
    media = models.ForeignKey(Media)

Now, I want to filter all videos which have a specific format, AND the status code for that format is 10 (ready to use). How can I do that? (assuming that f is the format):

f = Format.objects.get(pk=3)

I'm tempted to use:

Video.objects.filter(media__formats=f, media__mediaformat__status=10)

But then, that would return all videos that matches both of these assumptions:

• a) contain that specific format, and
• b) contain any format with the status of 10

How am I supposed to filter only those who have that specific format in a status code of 10?

thank you!

Answer 1

Now, I want to filter all videos which have a specific format, AND the status code for that format is 10 (ready to use). How can I do that? (assuming that f is the format)

The code you posted will do exactly what you want:

Video.objects.filter(media__formats=f, media__mediaformat__status=10)

This is documented in the filter() documentation:

Multiple parameters are joined via AND in the underlying SQL statement.