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Is many-to-many relationships with extra fields the right tool for my work?

I used to have the task of a more specific version of this question, but I could not formulate my question. On reflection, I questioned that my chosen solution was the right one for the problem, so this time I will explain the problem and ask: a) I am on the right path and b) if there is a path around my current brick wall.

I am currently creating a web interface that allows me to test an existing database (a small number) of users. Having an analogy with the docs, I have models that look something like this:

class Musician(models.Model):
    first_name = models.CharField(max_length=50)
    last_name = models.CharField(max_length=50)
    dob = models.DateField()

class Album(models.Model):
    artist = models.ForeignKey(Musician)
    name = models.CharField(max_length=100)

class Instrument(models.Model):
    artist = models.ForeignKey(Musician)
    name = models.CharField(max_length=100)

() , ForeignKey, OneToOneFields. , , . , , , . 2- ( ) .

, ~ 5000 20 .

, . , , ( ), , .

, , :

class UserDataSets(models.Model):
    user = models.ForeignKey(User)
    name = models.CharField(max_length=100)
    description = models.CharField(max_length=64)
    results = models.ManyToManyField(Musician, through='UserData')

class UserData(models.Model):
    artist = models.ForeignKey(Musician)
    dataset = models.ForeignKey(UserDataSets)
    score = models.IntegerField()

    class Meta:
        unique_together = (("artist", "dataset"),)

, , 1 1 "". , .

, . - :

artist = Musician.objects.get(pk=1)
dataset = UserDataSets.objects.get(pk=5)
print artist.userdata_set.get(dataset=dataset.pk)

, , single. , UserData :

artists = Musician.objects.all().order_by(userdata__score)

. , "" (, > 5 1 2 2).

, ?

0
1

edit: nevermind, . , , .

,

, - :

artists = Musician.objects.select_related('UserDataSets').filter( Q(userdata__score_gt=5, userdata__id=1) | Q(userdata__sorce_lt=2, userdata__id=2 )

, Q, : Q.

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