How to add ArrayField in Django? - django

Question

my models.py
class LiveClass_details(models.Model):
standard = models.ForeignKey(LiveClass, on_delete=models.CASCADE)
chapter_details = models.TextField(default='')
mentor_id = models.ForeignKey(Mentor, max_length=30, on_delete=models.CASCADE)
start_time = models.DateTimeField()
end_time = models.DateTimeField()
doubtClass = models.OneToOneField(DoubtClasses, on_delete=models.PROTECT, null=True, blank=True)
isDraft = models.BooleanField(default=True)
ratings = models.FloatField(default=0)
no_of_students_registered = models.IntegerField(default=0)
# registered_students = models.ManyToManyField(RegisteredNames, null=True, blank=True)
no_of_students_attended = models.IntegerField(default=0)
class Meta:
verbose_name_plural = 'LiveClass_details'
class RegisteredNames(models.Model):
name = models.CharField(max_length=100, unique=True)
liveclass_id = models.ForeignKey
I am creating a endpoint where when a user register himself his name will get added to registered_students , so i had made a registered students ManyToMany Field hoping it will get updated when a user is registered but then i understand that it will contain all the names that are present in the RegisteredNames Model meaning names registered across all the liveclasses but i want only the names that are registered for a particular liveclass in the field so i need a array like field which i think is not possible so please help me in improving my logic, how can i achieve it

Answer 1

The documentation and django tutorials are very good: https://docs.djangoproject.com/en/3.2/topics/db/models/ https://docs.djangoproject.com/en/3.2/intro/tutorial02/#creating-models
Your code is very close. You don’t need the many-to-many field, and you need to specify the type of the Foreign key relationship in the RegisteredNames. You can do this:
class LiveClass_details(models.Model):
standard = models.ForeignKey(LiveClass, on_delete=models.CASCADE)
chapter_details = models.TextField(default='')
mentor_id = models.ForeignKey(Mentor, max_length=30, on_delete=models.CASCADE)
start_time = models.DateTimeField()
end_time = models.DateTimeField()
doubtClass = models.OneToOneField(DoubtClasses, on_delete=models.PROTECT, null=True, blank=True)
isDraft = models.BooleanField(default=True)
ratings = models.FloatField(default=0)
no_of_students_attended = models.IntegerField(default=0)
class Meta:
verbose_name_plural = 'LiveClass_details'
class RegisteredNames(models.Model):
name = models.CharField(max_length=100, unique=True)
liveclass = models.ForeignKey(LiveClass_details, on_delete=Models.CASCADE)
Then, simply:
name = RegisteredNames.objects.create(name="Dhruv", liveclass_id=1)
To get all the registered names from a liveclass_details:
names = LiveClass_details.objects.get(id=1).registerednames_set.all()
num_reg = len(names)