Alembic¶
# a new column, model, etc. has been added before
alembic revision --autogenerate -m '<describe your changes>'
# review the migration in backend/feedback/alembic/versions
# upgrade to the latest version
alembic upgrade head
Make it a point to downgrade and upgrade whenever a change has a migration, to make sure nothing breaks.
Field length changes¶
Alembic doesn't detect field length changes by default, it's configuration has to be modified to detect it.
Setting up alembic to detect the column length change
Alembic - migration for String length change
Warning¶
Alembic can make errors when using context.configure(url=url, target_metadata=target_metadata, literal_binds=True, compare_type=True)
when using compare_type
.