How can I perform data migrations using Django ORM?

How can I perform data migrations using Django ORM?

You can perform data migrations in Django ORM by using the makemigrations and migrate commands. First, create a migration file with python manage.py makemigrations, then apply it with python manage.py migrate.

What if I need to add initial data during the migration?

You can add initial data by creating a data migration. Use the RunPython operation in your migration file to define a function that inserts the data.

Can you show me an example of a data migration?

Sure! Here's a simple example:

from django.db import migrations

def add_initial_data(apps, schema_editor):
    MyModel = apps.get_model('myapp', 'MyModel')
    MyModel.objects.create(name='Initial Data')

class Migration(migrations.Migration):
    dependencies = [
        ('myapp', '0001_initial'),
    ]

    operations = [
        migrations.RunPython(add_initial_data),
    ]

How do I roll back a migration if something goes wrong?

You can roll back a migration using the command python manage.py migrate myapp <migration_name>, where <migration_name> is the name of the migration you want to revert to.