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Python Django Basics Django Templates Add a Detail View

Oprea Mihai
Oprea Mihai
5,592 Points
Posted by Oprea Mihai
Oprea Mihai
5,592 Points

ForeignKey

When I run Step with ForeignKey in my Pycharm i get an __init()__ error. Can you help me ?

class Step(models.Model):
    title=models.CharField(max_length=255)
    description=models.TextField()
    order=models.IntegerField(default=0) 
    course=models.ForeignKey(Course) 


    def __str__(self):
        return self.title

# error:
TypeError: __init__() missing 1 required positional argument: 'on_delete'

[MOD: Added ``` python formatting and ` escapes on the dunder -cf]

2 Answers

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,454 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,454 Points

Starting in Django 2.0, the on_delete is required for ForeignKeys. Change your usage to:

    course=models.ForeignKey(Course, on_delete=models.DO_NOTHING, )

Information in the Django docs ForeignKey.

I found the original help on this JetBrains forum post