I have been researching and looking through all the docs but I am still a bit confused, I think maybe because there are multiple ways to use the OnToOneField.
I have 4 models, Pregame, Ingame, Postgame and Game. And I want 'Game' to contain the other three models.
As of right now it looks like this...
class Pregame(models.Model):
game_id = models.CharField(max_length=10)
other fields...
def __str__(self):
return str(self.game_id)
class Ingame(models.Model):
game_id = models.CharField(max_length=10)
other fields...
def __str__(self):
return str(self.game_id)
class Postgame(models.Model):
game_id = models.CharField(max_length=10)
other fields...
def __str__(self):
return str(self.game_id)
class Game(models.Model):
game_id = models.CharField(max_length=10)
pregame = models.OneToOneField(
Pregame, on_delete=models.CASCADE, null=True)
ingame = models.OneToOneField(
Ingame, on_delete=models.CASCADE, null=True)
postgame = models.OneToOneField(
Postgame, on_delete=models.CASCADE, null=True)
def __str__(self):
return str(self.game_id)
I am using OnToOne because each Game will only have one Pregame, Ingame and Postgame and the other three models will only belong to one Game.
I have a couple questions I am confused about.
Will I be able to have a Game object if one of the other model objects doesn't exist yet? Like if there is a Pregame but no Ingame or Postgame, will Game still exist with just Pregame inside of it? I seen a couple videos where they did a default='{}', is that what I should be doing?
Each model has game_id and that is how I am connecting them all together into the'Game' object. Is there a OneToOneField option like game_id=game_id so the 'Game' model will automatically link all the models together or would I still have to do that separate?
Thank you for your help and knowledge.
First of all, you don't have to set game_id on the *game entities. You can just add related_name:
class Game(models.Model):
game_id = models.CharField(max_length=10)
pregame = models.OneToOneField(
Pregame, on_delete=models.CASCADE, null=True, related_name="game")
ingame = models.OneToOneField(
Ingame, on_delete=models.CASCADE, null=True, related_name="game")
postgame = models.OneToOneField(
Postgame, on_delete=models.CASCADE, null=True, related_name="game")
class Pregame(models.Model):
other fields...
def __str__(self):
return str(self.game_id)
Will I be able to have a Game object if one of the other model objects doesn't exist yet? Like if there is a Pregame but no Ingame or Postgame, will Game still exist with just Pregame inside of it? I seen a couple videos where they did a default='{}', is that what I should be doing?
Yes, a Game object can exist even without a *game, as you added null=True. You should use a default when your model does not accept null/empty values.
Each model has game_id and that is how I am connecting them all together into the'Game' object. Is there a OneToOneField option like game_id=game_id so the 'Game' model will automatically link all the models together or would I still have to do that separate?
Once you create such a model, you have access via the Game entity. For example from going to pregame to postgame:
postgame = pregame.game.postgame