Question

I’m working with an OS project that uses South to migrate the database.
I’m building a new database from scratch and I want to make sure South is setup so I can easily update the database in the future.

It seems this process should be:

1. create the db
2. syncdb
3. migrate

However, when I try to migrate the databases, one of the the earlier migrations(migration 0004 and they go to 0009) throws an exception:

ValueError: You cannot add a null=False column without a default value.

I don’t understand how to add a default value to migration 0004 so this exception isn’t thrown.

The migrations don’t need to be run through because the database is empty.

However, south_migrationhistory must contain a list of all migrations and when they were applied.

I tried to hack it and just add migration 0009 to the database manually, but this threw another error because the intermediary migrations had not been run.
I also tried to add a field to database to see if I could figure out the syntax of add_column would look like with a default value of 0 supplied.
The format looks totally different than these older migrations.

Here are the 2 different versions of the add_column syntax:

#0004 syntax:  
db.add_column('experiments_dailyreport', 'test_group_size', orm['experiments.dailyreport:test_group_size'])
#0009 syntax:
syntax db.add_column('experiments_dailyreport', 'test_group_size', self.gf('django.db.models.fields.IntegerField')(default=0), keep_default=False)

So, I’m guessing there was a change in the South code between when 0004 was created and today.

Is there a way to build the database with syncdb and then somehow update south_migrationhistory without running manage.py migrate ?

If you have an existing app with South migrations, how would you build a new database from scratch?

I can’t migrate because there is no default set on a integer field.
How do I set a default in an older migration? The field doesn’t even exist anymore.

syntaxes attempted:

db.add_column('experiments_dailyreport', 'test_group_size', orm['experiments.dailyreport:test_group_size'], {'default': 0})
#throws ValueError: You cannot add a null=False column without a default value.
db.add_column('experiments_dailyreport', 'test_group_size', self.gf('django.db.models.fields.IntegerField')(default=0), keep_default=False)
#throws AttributeError: Migration instance has no attribute 'gf'

I’m using South-0.7.2-py2.7.egg

Answer 1

Andrew Godwin provided an answer:

Yes, use:

./manage.py syncdb --all  

then:

./manage.py migrate --fake  

This will, however, also ignore any migrations that add in data to the database.