I have a Django model that has a foreign key to another model:
class Example(models.Model)
something = models.ForeignKey(SomeModel, db_index=True)
I want to keep the underlying DB column as a field, but to get rid of the foreign key constraint in the database.
So the model will change to:
class Example(models.Model):
something_id = models.IntegerField()
And, to be clear, something_id
is the column that Django had created for the foreign key field.
I do not want to drop the column and re-create it (this is what Django does when I auto-generate migrations after changing the model as above).
I want to keep the field but I want to remove the foreign key constraint in the database with a migration. It's not clear to me how to do this with a Django migration - is there some built in support for it or do I have to run some raw SQL and, if so, how do I programatically get the name of the constraint?
This is how I managed to do it, it's based on nimasmi's answer above:
class Migration(migrations.Migration):
dependencies = [
('my_app', '0001_initial'),
]
# These *WILL* impact the database!
database_operations = [
migrations.AlterField(
model_name='Example',
name='something',
field=models.ForeignKey('Something', db_constraint=False, db_index=True, null=False)
),
]
# These *WON'T* impact the database, they update Django state *ONLY*!
state_operations = [
migrations.AlterField(
model_name='Example',
name='something',
field=models.IntegerField(db_index=True, null=False)
),
migrations.RenameField(
model_name='Example',
old_name='something',
new_name='something_id'
),
]
operations = [
migrations.SeparateDatabaseAndState(
database_operations=database_operations,
state_operations=state_operations
)
]