Flask-migrate: Migrate doesn't create default value

[omni-vi]

Hi Miguel,

I just added the following line to my model.
customerComment = db.Column(db.String(500), nullable=False, default="")

The resulting line in my migration script is
op.add_column('angebot', sa.Column('customerComment', sa.String(length=500), nullable=False))

There is no default value, which leads to the following error:
sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) Cannot add a NOT NULL column with default value NULL [SQL: 'ALTER TABLE angebot ADD COLUMN "customerComment" VARCHAR(500) NOT NULL'] (Background on this error at: http://sqlalche.me/e/e3q8)

Even stranger, I have a field
country = db.Column(db.String(2), nullable=False, default="DE")
and the resulting script line is
op.add_column('user', sa.Column('country', sa.String(length=2), nullable=False))

Am I doing something wrong? Should I use a different default value?
Thanks for your work!

[miguelgrinberg]

The default value is something that is done at the SQLAlchemy level. If you want the database to insert the default value, use server_default.

[omni-vi]

Thank you.