Question

I’m trying to figure out how to execute the following sql join statement in Django without resorting to just raw sql. Is there a way to do it?

Select * from playertable, seasontable where player.id = season.player_id

Here are my models. Just to clarify, I used abbreviated table names in the above query for clarify

class Player(models.Model): 
    name = models.CharField(max_length=200)
    team = models.CharField(max_length=3)
    position = models.CharField(max_length=3)

class PlayerSeason(models.Model):

    player = models.ForeignKey(Player)
    year = models.IntegerField()
    games_played = models.IntegerField()
    goals = models.IntegerField()
    assists = models.IntegerField()
    points = models.IntegerField()
    plusminus = models.CharField(max_length=200)
    pim = models.IntegerField()
    ppg = models.IntegerField()
    shg = models.IntegerField()
    gwg = models.IntegerField()
    otg = models.IntegerField()
    shots = models.IntegerField()
    shooting_percentage = models.DecimalField(max_digits=5, decimal_places=2)
    toi = models.CharField(max_length=200)
    sftg = models.DecimalField(max_digits=5, decimal_places=2)
    face_off = models.DecimalField(max_digits=5, decimal_places=2)

How should I do this with a Django QuerySet?

Answer 1

If all you wanted to do was to get all the players associated with a given season you could make use of Django’s backwards relationships

When you use a ForeignKeyField to a model, in this case Season, the that model instances get an attribute which allows you to get a queryset of all the related objects.

In your example you could use season.player_set.all().

You can pass an optional parameter related_name to the ForeignKeyField that allows you to change the name of the season attribute.