[Answered ]-I'm getting an error message when making migration to db in django

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0👍

✅

This was caused because you’re trying to migrate a model field that cannot be null, but since it cannot be null, it needs a default value so that django can replace all the existing rows with the null value of that field.

You have two options:

  1. Provide the default by hand, and the django it’s going to replace all the null values of that field with this

  2. Set a default value in the model, example:

number = models.IntegerField(default=1)

string = models.CharField(default='')

👤Bruno Urbano

1👍

first approach

  • this comes because you run the migration on each field created so the previous created filled doesn’t accept null value so you want to provide default value in your case it is string value
  • you can choose the first choice and but the answer to be "default" with a quotation to understand it as a string

The second solution

delete the latest file created in the migration folder and
modify your model to be

'''
name = models.CharField(max_length=100,null=True) 
details = models.CharField(max_length=500, null=True) 
'''

then run the migration again

python manage.py makemigration
python manage.py migrate
then go back to model again and remove null from each field and run
python manage.py makemigration
python manage.py migrate

👤Mohamed Beltagy

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